QUIZ 7

1. Discuss the components required for successful communications.

Sender, beneficiary, and a atmosphere. That's in the order of the most chief definition of the components of computer network.

2. Identify various sending and receiving devices.

Sending device initiates the transmission of data, instructions, and information while a receiving device accepts the items transmitted.

·        Microcomputers

·        Minicomputers

·        Mainframes

·        Internet appliances and web enabled handheld computers

3. Describe uses of computer communications.

 4. List advantages of using a network.

<!--[if !supportLists]-->·                               <!--[endif]-->share software

<!--[if !supportLists]-->·                               <!--[endif]-->share information with others on networks

<!--[if !supportLists]-->·                               <!--[endif]-->share peripherals

<!--[if !supportLists]-->·                               <!--[endif]-->speed of sharing software and information files

<!--[if !supportLists]-->·                               <!--[endif]-->cheaper than buying individual software and hardware for each standalone especially if for a school, network software often offers deals for amount being purchased

<!--[if !supportLists]-->·                               <!--[endif]-->security, files can be copy inhibit mode

<!--[if !supportLists]-->·                               <!--[endif]-->centralized software management- software being loaded onto one computer but also this loads software to entire network at one time

<!--[if !supportLists]-->·                               <!--[endif]-->electronic mail(e-mail) between network users, ideal for office memos

<!--[if !supportLists]-->·                               <!--[endif]-->flexible access- access you files from any computer on the network unlike standalone which would mean only being able to access your data from the one computer you uploaded data onto

5. Differentiate among client/server, peer-to-peer, and P2P networks.

Client/server-describes the relationship between two computer programs in which one program, the client, makes a service request from another program, the server, which fulfills the request.

Peer-to-peer (P2P)-computing or networking is a distributed application architecture that partitions tasks or workloads between peers. Peers are equally privileged, equipotent participants in the application. They are said to form a peer-to-peer network of nodes.

6. Describe the various network communications standards.

7. Explain the purpose of communications software.
Communication software is used to provide remote access to systems and is also used to exchange messages in text, audio and video format for the purpose of communication. This software sends and receives data over telephone lines through modems. The communication software allows computers in different geographical regions to communicate with each other through terminal emulators, file transfer programs, chat and instant messaging programs.

8. Describe various types of lines for communications over the telephone network.

9. Describe commonly used communications devices.

Radios are communication systems that send and/or receive electromagnetic waves and consist of a transmitter, receiver, and antenna. Pagers are electronic communications devices that are used to notify or alert a user. Communication received by pagers may be numeric or alphanumeric, depending on the model and complexity of the device.

Other types of communication devices include navigation systems, such as global positioning systems (GPS) instruments and radar systems. GPS communication devices receive satellite communications and use it to provide position information. Radar communication devices use synchronized transmitters and receivers to send radio waves and detect their reflections from objects, surfaces and sub-surface structures.

10. Discuss different ways to set up a home network.

11. Identify various physical and wireless transmission media.

For physical transmission Media there are:

<!--[if !supportLists]-->1.   <!--[endif]-->Twisted-Pair Cable

<!--[if !supportLists]-->2.   <!--[endif]-->Coaxial Cable

<!--[if !supportLists]-->3.   <!--[endif]-->Fiber-Optic Cable

For wireless trasmission media there are:

i. Broadcast Radio
ii. Cellular Radio
iii. Microwaves
iv. Communication Satellite

1.

2. Identify various sending and receiving devices.

1. System software is computer software designed to operate the computer hardware and to provide a platform for running application software.
The most basic types of system software are:

• The computer BIOS and device firmware, which provide basic functionality to operate and control the hardware connected to or built into the computer.
• The operating system (prominent examples being Microsoft Windows, Mac OS X and Linux), which allows the parts of a computer to work together by performing tasks like transferring data between memory and disks or rendering output onto a display device. It also provides a platform to run high-level system software and application software.
• Utility software, which helps to analyze, configure, optimize and maintain the computer.

In some publications, the term system software is also used to designate software development tools (like a compiler, linker or debugger).
In contrast to system software, software that allows users to do things like create text documents, play games, listen to music, or surf the web is called application software.

Types of system software programs

System software helps use the operating system and computer system.

2. Windows Server is a brand name for a group of server operating systems released by Microsoft Corporation. All are part of Microsoft Servers. This brand includes the following software:

• Windows Server 2003
• Windows Server 2008
  • Windows HPC Server 2008, an edition designed exclusively for high-performance computing
  • Windows Server 2008 R2, the current release of Windows Server 2008
• Windows Small Business Server, an operating system based on Windows Server with some integrated Microsoft Servers, for small businesses
• Windows Essential Business Server, a product similar to Small Business Server, but for medium-sized businesses
• Windows Home Server, a home server operating system for file sharing and streaming, automated backups, and remote access
  • Windows Home Server 2011, a home server operating system designed for Small Office/Home Office (SOHO)
• Windows MultiPoint Server, a product allowing multiple simultaneous local users.

Unix (officially trademarked as UNIX, sometimes also written as Unix) is a multitasking, multi-user computer operating system originally developed in 1969 by a group of AT&T employees at Bell Labs, including Ken Thompson, Dennis Ritchie, Brian Kernighan, Douglas McIlroy, and Joe Ossanna. The Unix operating system was first developed in assembly language, but by 1973 had been almost entirely recoded in C, greatly facilitating its further development and porting to other hardware. Today's Unix systems are split into various branches, developed over time by AT&T as well as various commercial vendors and non-profit organizations. The second edition of Unix was released on December 6th, 1972.
Linux (commonly  /ˈlɪnəks/ lin-əks in English, also pronounced /ˈlɪnʊks/ lin-uuks in Europe) refers to the family of Unix-like computer operating systems using the Linux kernel. Linux can be installed on a wide variety of computer hardware, ranging from mobile phones, tablet computers, routers and video game consoles, to desktop computers, mainframes and supercomputers. Linux is a leading server operating system, and runs the 10 fastest supercomputers in the world. The development of Linux is one of the most prominent examples of free and open source software collaboration; typically all the underlying source code can be used, freely modified, and redistributed, both commercially and non-commercially, by anyone under licenses such as the GNU General Public License. Typically Linux is packaged in a format known as a Linux distribution for desktop and server use. Some popular mainstream Linux distributions include Debian (and its derivatives such as Ubuntu), Fedora and openSUSE. Linux distributions include the Linux kernel, supporting utilities and libraries and usually a large amount of application software to fulfill the distribution's intended use.
Solaris is a Unix operating system originally developed by Sun Microsystems. It superseded their earlier SunOS in 1993. Oracle Solaris, as it is now known, has been owned by Oracle Corporation since Oracle's acquisition of Sun in January 2010. Solaris is known for its scalability, especially on SPARC systems, and for originating many innovative features such as DTrace, ZFS and Time Slider.^[3][4] Solaris supports SPARC-based and x86-based workstations and servers from Sun and other vendors, with efforts underway to port to additional platforms. Solaris is registered as compliant with the Single Unix Specification.
NetWare is a network operating system developed by Novell, Inc. It initially used cooperative multitasking to run various services on a personal computer, with network protocols based on the archetypal Xerox Network Systems stack.

3. Windows Embedded CE is optimized for devices that have minimal storage—a Windows CE kernel may run in under a megabyte of memory. Devices are often configured without disk storage, and may be configured as a “closed” system that does not allow for end-user extension (for instance, it can be burned into ROM). Windows CE conforms to the definition of a real-time operating system, with a deterministic interrupt latency. From version 3 and onward, the system supports 256 priority levels and uses priority inheritance for dealing with priority inversion. The fundamental unit of execution is the thread. This helps to simplify the interface and improve execution time.
Microsoft has stated that the ‘CE’ is not an intentional initialism, but many people believe CE stands for ‘Consumer Electronics’ or ‘Compact Edition’. Microsoft says the letters instead imply a number of Windows CE design precepts, including “Compact, Connectable, Compatible, Companion, and Efficient." The first version, known during development under the code name “Pegasus”, featured a Windows-like GUI and a number of Microsoft's popular applications, all trimmed down for smaller storage, memory, and speed of the palmtops of the day.
Since then, Windows CE has evolved into a component-based, embedded, real-time operating system. It is no longer targeted solely at hand-held computers. Many platforms have been based on the core Windows CE operating system, including Microsoft's AutoPC, Pocket PC 2000, Pocket PC 2002, Windows Mobile 2003, Windows Mobile 2003 SE, Windows Mobile 5.0, Windows Mobile 6, Smartphone 2002, Smartphone 2003, Portable Media Center, Zune, Windows Phone 7 and many industrial devices and embedded systems. Windows CE even powered select games for the Dreamcast, was the operating system of the Gizmondo handheld, and can partially run on modified Xbox game consoles.
A distinctive feature of Windows CE compared to other Microsoft operating systems is that large parts of it are offered in source code form. First, source code was offered to several vendors, so they could adjust it to their hardware. Then products like Platform Builder (an integrated environment for Windows CE OS image creation and integration, or customized operating system designs based on CE) offered several components in source code form to the general public. However, a number of core components that do not need adaptation to specific hardware environments (other than the CPU family) are still distributed in binary only form.
Windows Mobile for Pocket PC have these standard features:

• Today screen shows the current date, owner information, upcoming appointments, e-mail messages, and tasks. (Home screen in later WM6.5 builds)
• The taskbar shows the current time and the audio volume.
• Office Mobile, a suite of Mobile versions of Microsoft Office applications, including Outlook Mobile.
• Internet Explorer Mobile, an Internet browser developed by Microsoft for Pocket PC and Handheld PC that comes loaded by default with Windows Mobile and Windows CE for Handheld PC.
• Windows Media Player for Windows Mobile.
• Client for PPTP VPNs.
• Internet Connection Sharing (ICS), which in mobile phones allows the phone to make its Internet connection available to computers via USB and Bluetooth.
• File system similar to that of Windows 9x/Windows NT, with support for many of the same file types.
• Ability to multitask.

Palm OS Garnet has the following features:

• Simple, single-tasking environment to allow launching of full screen applications with a basic, common GUI set
• Monochrome or color screens with resolutions up to 480x320 pixel
• Handwriting recognition input system called Graffiti 2
• HotSync technology for data synchronization with desktop computers
• Sound playback and record capabilities
• Simple security model: Device can be locked by password, arbitrary application records can be made private
• TCP/IP network access
• Serial port/USB, infrared, Bluetooth and Wi-Fi connections
• Expansion memory card support
• Defined standard data format for personal information management applications to store calendar, address, task and note entries, accessible by third-party applications.

Included with the OS is also a set of standard applications, with the most relevant ones for the four mentioned PIM operations.
iPhone OS features the following:
Home screen
The home screen (rendered by "SpringBoard") displays application icons and a dock at the bottom of the screen where users can pin their most frequently used apps. The home screen appears whenever the user switches on the device or presses the "Home" button (a physical button on the device). The screen has a status bar across the top to display data, such as time, battery level, and signal strength. The rest of the screen is devoted to the current application.
Since iOS version 3.0, a Spotlight Search function has been available on the home screen, allowing users to search through media, applications, emails, contacts and similar files.

Folders

With iOS 4 came the introduction of a simple foldering system. When applications are in "wiggle mode", any two can be dragged on top of each other to create a folder, and from then on, any other 10 "apps" can be added to the folder using the same procedure (maximum folders can handle is 12 on iPhone and iPod touch and 20 on iPad). A title for the folder is automatically selected by the type of applications inside, but the name can also be edited by the user.

Notifications screen

In the iOS 5 update, the notifications feature has been revamped. Notifications now collate in a window which can be dragged down from the top of the screen (in a similar fashion to the Android OS).

Included applications

The iOS home screen contains these default "apps". Some of these applications are hidden by default and accessed by the user through the Settings app or another method—for instance, Nike+iPod is activated through the Settings app. All of the utilities, such as voice memos, clock, calculator, and compass are in one folder called "Utilities" in 4.0. Many of the included applications are designed to share data (e.g., a phone number can be selected from an email and saved as a contact or dialed for a phone call).
The iPod touch retains the same applications that are present by default on the iPhone, with the exception of the Phone, Messages, Compass and Camera (prior to the 4th generation) apps. The "iPod" App present on the iPhone is split into two apps on the iPod Touch: Music, and Videos. The bottom row of applications is also used to delineate the iPod touch's main purposes: Music, Videos, Safari, and App Store (Dock Layout was changed in 3.1 Update). For the 4th Generation iPod touch, it includes FaceTime and Camera, and the dock layout had changed to Music, Mail, Safari, Video. As of iOS 5.0 (to be released to the public in fall 2011), "iMessage" will be available on all iOS devices running iOS 5. iMessage is effectively a version of the iPhone Messages app that sends free text or multimedia messages to other iOS devices (similar to BlackBerry Messenger).
The iPad comes with the same applications as the iPod touch excluding Stocks, Weather, Clock, Calculator, and the Nike + iPod app. Separate music and video apps are provided, as on the iPod touch, although (as on the iPhone) the music app is named "iPod". In iOS 5, the iPod app will be replaced by Music and Video apps on all devices. Most of the default applications are completely rewritten to take advantage of the iPad's larger display. The default dock layout includes Safari, Mail, Photos and iPod.

Multitasking

Before iOS 4, multitasking was limited to a selection of the applications Apple included on the devices. Apple worried that running multiple third-party applications simultaneously would drain batteries too quickly. Starting with iOS 4, on 3rd-generation and newer iOS devices, multitasking is supported through seven background APIs:

1. Background audio
2. Voice over IP
3. Background location
4. Push notifications
5. Local notifications
6. Task finishing
7. Fast app switching

Switching applications

Double-pressing the home button activates the application switcher. A scrollable dock-like interface appears from the bottom, moving the contents of the screen up. Choosing an icon switches to an application. To the far left are icons which function as music controls, and a rotation lock. Holding the icons briefly makes them wiggle (similarly to the homescreen) and allows the user to quit the applications.

Game Center

Main article: Game Center

Game Center is an online multiplayer "social gaming network" released by Apple. It allows users to "invite friends to play a game, start a multiplayer game through matchmaking, track their achievements, and compare their high scores on a leader board."
Game Center was announced during an iOS 4 preview event hosted by Apple on April 8, 2010. A preview was released to registered Apple developers in August. It was released on September 8, 2010 with iOS 4.1 on iPhone 4, iPhone 3GS and iPod touch 2nd generation through 4th generation. Game Center made its public debut on the iPad with iOS 4.2.1. There will be no support for the iPhone 3G and original iPhone. However, Game Center is unofficially available on the iPhone 3G via a hack.
BlackBerry OS is a proprietary mobile operating system, developed by Research In Motion for its BlackBerry line of smartphone handheld devices. The operating system provides multitasking and supports specialized input devices that have been adopted by RIM for use in its handhelds, particularly the trackwheel, trackball, and most recently, the trackpad and touchscreen. The BlackBerry platform is perhaps best known for its native support for corporate email, through MIDP 1.0 and, more recently, a subset of MIDP 2.0, which allows complete wireless activation and synchronization with Microsoft Exchange, Lotus Domino, or Novell GroupWise email, calendar, tasks, notes, and contacts, when used with BlackBerry Enterprise Server. The operating system also supports WAP 1.2. Updates to the operating system may be automatically available from wireless carriers that support the BlackBerry over the air software loading (OTASL) service. Third-party developers can write software using the available BlackBerry API classes, although applications that make use of certain functionality must be digitally signed. As of 2011, many developers are using the BlackBerry platform to develop their applications. A June 2011 research indicates that approximately 45% of mobile developers were using the platform at the time of publication.

Google Android features the following:

Handset layouts	The platform is adaptable to larger, VGA, 2D graphics library, 3D graphics library based on OpenGL ES 2.0 specifications, and traditional smartphone layouts.
Storage	SQLite, a lightweight relational database, is used for data storage purposes
Connectivity	Android supports connectivity technologies including GSM/EDGE, IDEN, CDMA, EV-DO, UMTS, Bluetooth, Wi-Fi (no connections through Proxy server and no Ad hoc wireless network), LTE, NFC and WiMAX.
Messaging	SMS and MMS are available forms of messaging, including threaded text messaging and now Android Cloud To Device Messaging Framework(C2DM) is also a part of Android Push Messaging service.
Multiple language support	Android supports multiple human languages. The number of languages more than doubled for the platform 2.3 Gingerbread. Android lacks font rendering of several languages even after official announcements of added support (e.g. Hindi).
Web browser	The web browser available in Android is based on the open-source WebKit layout engine, coupled with Chrome's V8 JavaScript engine. The browser scores a 93/100 on the Acid3 Test.
Java support	While most Android applications are written in Java, there is no Java Virtual Machine in the platform and Java byte code is not executed. Java classes are compiled into Dalvik executables and run on Dalvik, a specialized virtual machine designed specifically for Android and optimized for battery-powered mobile devices with limited memory and CPU. J2ME support can be provided via third-party applications.
Media support	Android supports the following audio/video/still media formats: WebM, H.263, H.264 (in 3GP or MP4 container), MPEG-4 SP, AMR, AMR-WB (in 3GP container), AAC, HE-AAC (in MP4 or 3GP container), MP3, MIDI, Ogg Vorbis, FLAC, WAV, JPEG, PNG, GIF (though earlier versions do not support animated GIFs), BMP.
Streaming media support	RTP/RTSP streaming (3GPP PSS, ISMA), HTML progressive download (HTML5 <video> tag). Adobe Flash Streaming (RTMP) and HTTP Dynamic Streaming are supported by the Flash plugin. Apple HTTP Live Streaming is supported by RealPlayer for Mobile, and by the operating system in Android 3.0 (Honeycomb). Microsoft Smooth Streaming is planned to be supported through the awaited port of Silverlight plugin to Android.
Additional hardware support	Android can use video/still cameras, touchscreens, GPS, accelerometers, gyroscopes, magnetometers, dedicated gaming controls, proximity and pressure sensors, thermometers, accelerated 2D bit blits (with hardware orientation, scaling, pixel format conversion) and accelerated 3D graphics.
Multi-touch	Android has native support for multi-touch which was initially made available in handsets such as the HTC Hero. The feature was originally disabled at the kernel level (possibly to avoid infringing Apple's patents on touch-screen technology at the time). Google has since released an update for the Nexus One and the Motorola Droid which enables multi-touch natively.
Bluetooth	Supports A2DP, AVRCP, sending files (OPP), accessing the phone book (PBAP), voice dialing and sending contacts between phones. Keyboard, mouse and joystick (HID) support is available through manufacturer customizations and third-party applications. Full HID support is planned for Android 3.0 (Honeycomb).
Video calling	Android does not support native video calling, but some handsets have a customized version of the operating system that supports it, either via the UMTS network (like the Samsung Galaxy S) or over IP. Video calling through Google Talk is available in Android 2.3.4 and later.
Multitasking	Multitasking of applications is available.
Voice based features	Google search through voice has been available since initial release. Voice actions for calling, texting, navigation, etc. are supported on Android 2.2 onwards.
Tethering	Android supports tethering, which allows a phone to be used as a wireless/wired hotspot. Before Android 2.2 this was supported by third-party applications or manufacturer customizations.
Screen capture	Android does not support screenshot capture as of 2011. This is supported by manufacturer and third-party customizations.

Embedded Linux is the use of Linux in embedded computer systems such as mobile phones, personal digital assistants, media players, set-top boxes, and other consumer electronics devices, networking equipment, machine control, industrial automation, navigation equipment and medical instruments. According to survey conducted by Venture Development Corporation, Linux was used by 18% of embedded engineers. Linux has been ported to a variety of CPUs not primarily used as the processor of a desktop or server computer, including ARM, AVR32, ETRAX CRIS, FR-V, H8300, IP7000, m68k, MIPS, mn10300, SuperH, and Xtensa processors, as an alternative to using a proprietary operating system and toolchain. The advantages of embedded Linux over proprietary embedded operating systems include no royalties or licensing fees, a stable kernel, a support base that is not restricted to the employees of a single software company, and the ability to modify and redistribute the source code. The disadvantages include a comparatively larger memory footprint (kernel and root filesystem), complexities of user mode and kernel mode memory access, and complex device drivers framework.
User interface

Symbian has had a native graphics toolkit since its inception, known as AVKON (formerly known as Series 60). S60 was designed to be manipulated by a keyboard-like interface metaphor, such as the ~15-key augmented telephone keypad, or the mini-QWERTY keyboards. AVKON-based software is binary-compatible with Symbian versions up to and including Symbian^3.
Symbian^3 includes the Qt framework, which is now the recommended user interface toolkit for new applications. Qt can also be installed on older Symbian devices.
Symbian^4 was planned to introduce a new GUI library framework specifically designed for a touch-based interface, known as "UI Extensions for Mobile" or UIEMO (internal project name "Orbit"), which was built on top of Qt; a preview was released in January 2010, however in October 2010 Nokia announced that Orbit/UIEMO has been cancelled.
Nokia currently recommends that developers use Qt Quick with QML, the new high-level GUI and scripting framework for creating visually rich touchscreen interfaces that allows development for both Symbian and MeeGo; it will be delivered to existing Symbian^3 devices as a Qt update. When more applications gradually feature a user interface reworked in Qt, the legacy S60 framework (AVKON) will be deprecated and no longer included with new devices at some point, thus breaking binary compatibility with older S60 applications.

Browser

Main articles: S60 browser and Opera Mobile

Symbian^3 and earlier have a native WebKit based browser; indeed, Symbian was the first mobile platform to make use of WebKit (in June 2005). Some older Symbian models have Opera Mobile as their default browser.
Nokia plans to introduce a new Qt-based browser as a free firmware update for Symbian^3 devices and selected older models.

Application development

From 2010, Symbian switched to using standard C++ with Qt as the SDK, which can be used with either Qt Creator or Carbide. Qt supports the older Symbian S60 3rd and 5th editions, as well as the new Symbian platform. It also supports Maemo and MeeGo, Windows, Linux and Mac OS X.
Alternative application development can be done using Python (see Python for S60), Adobe Flash or Java ME.
Symbian OS previously used a Symbian specific C++ version along with Carbide.c++ integrated development environment (IDE) as the native application development environment.
Web Runtime (WRT) is a portable application framework that allows creating widgets on the S60 Platform; it is an extension to the S60 WebKit based browser that allows launching multiple browser instances as separate JavaScript applications.

4. A file manager or file browser is a computer program that provides a user interface to work with file systems. The most common operations performed on files or groups of files are: create, open, edit, view, print, play, rename, move, copy, delete, search/find, and modify attributes, properties and permissions. Files are typically displayed in a hierarchy. Some file managers contain features inspired by web browsers, including forward and back navigational buttons. Some file managers provide network connectivity via protocols, such as FTP, NFS, SMB or WebDAV. This is achieved by allowing the user to browse for a file server (connecting and accessing the server's file system like a local file system) or by providing its own full client implementations for file server protocols.
An image viewer or image browser is a computer program that can display stored graphical image; it can often handle various graphics file formats. Such software usually renders the image according to properties of the display such as color depth, display resolution, and color profile. Although you may use a full-featured bitmap graphics editor (such as Photoshop or the GIMP) as an image viewer, these have many editing functionalities which are not needed for just viewing images, and therefore usually start rather slowly. Also, most viewers have functionalities that editors usually lack, such as stepping through all the images in a directory (possibly as a slideshow). Image viewers give maximal flexibility to the user by providing a direct view of the directory structure available on a hard disk. Most image viewers do not provide any kind of automatic organization of pictures and therefore the burden remains on the user to create and maintain their folder structure (using tag- or folder-based methods). However, some image viewers also have features for organizing images, especially an image database, and hence can also be used as image organizers.
An uninstaller, also called a deinstaller, is a utility software designed to remove other software or parts of it from a computer. It is the opposite of an installer.
Disk Cleanup (cleanmgr.exe) is a computer maintenance utility included in Microsoft Windows designed to free up disk space on a computer's hard drive. The utility first searches and analyzes the hard drive for files that are no longer of any use, and then removes the unnecessary files.
Disk Defragmenter is a utility in Microsoft Windows designed to increase access speed by rearranging files stored on a disk to occupy contiguous storage locations, a technique called defragmentation. Defragmenting a disk minimizes head travel, which reduces the time it takes to read files from and write files to the disk. Beginning with Windows XP, Disk Defragmenter also reduces system startup times.
Backup and restore utility are computer programs used to perform backup; they create supplementary exact copies of files, databases or entire computers. These programs may later use the supplementary copies to restore the original contents in the event of data loss.
A screensaver is a type of computer program initially designed to prevent phosphor burn-in on CRT and plasma computer monitors by blanking the screen or filling it with moving images or patterns when the computer is not in use. Contemporary screensavers are used primarily for entertainment or security.
Decades before the first computers utilizing this technology were invented, Robert A. Heinlein postulated that they would be needed in Stranger In A Strange Land.
A personal firewall is an application which controls network traffic to and from a computer, permitting or denying communications based on a security policy.
Antivirus or anti-virus software is used to prevent, detect, and remove malware, including but not limited to computer viruses, computer worm, trojan horses, spyware and adware. This page talks about the software used for the prevention and removal of such threats, rather than computer security implemented by software methods.
Spyware and adware removers

1. They can provide real time protection against the installation of spyware software on the computer. This type of spyware protection works the same way as that of anti-virus protection in that the anti-spyware software scans all incoming network data for spyware software and blocks any threats it comes across.
2. Anti-spyware software programs can be used solely for detection and removal of spyware software that has already been installed onto the computer. This type of spyware protection is normally much easier to use and more popular. With this spyware protection software the user can schedule weekly, daily, or monthly scans of the computer to detect and remove any spyware software that have been installed on the computer. This type of anti-spyware software scans the contents of the windows registry, operating system files, and installed programs on the computer and will provide a list of any threats found, allowing the user to choose what to delete and what to keep.
3. Programs have been developed to detect, quarantine, and remove spyware, including Ad-Aware, Malwarebytes' Anti-Malware, Spyware Doctor and Spybot - Search & Destroy. In addition, almost all commercial antivirus software currently detect adware and spyware, or offer a separate spyware detection package. The reluctance to add adware and spyware detection to commercial antivirus products was fueled by a fear of lawsuits. Kaspersky, for example, was sued by Zango for blocking the installation of their products. Zango software and components are almost universally detected as adware nowadays.

Internet filters are software tools that can help monitor web content viewed on a particular computer or network. In the case of family safety settings, Internet filters can also help parents manage who kids can communicate with or how long kids can use the computer.
Media player is a term typically used to describe computer software for playing back multimedia files. While many media players can play both audio and video, others focus only on one media type or the other. Such players are known as either audio players or video players and often have a user interface tailored for the specific media type.
Media players often display icons known from physical devices such as tape recorders and CD players. Examples of these icons are (play), (pause), and (stop).
Personal Computer maintenance is the practice of keeping computers in a good state of repair.