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SALMAN GUJJAR

SALMAN GUJJAR

Search Utility

A web search engine is designed to search for information on the World wide web and FTP servers. The search results are generally presented in a list of results often referred to as SERPS, or “search engine results pages”. The information may consist of web pages, images, information and other types of files. Some search engines also mine data available in databases or open directories. Unlike web directories, which are maintained by human editors, search engines operate algorithmically or are a mixture of algorithmic and human input.

Operation

A search engine operates in the following order:

1. Web crawling.
2. Indexing.
3. Searching.

Web search engines work by storing information about many web pages, which they retrieve from the html itself. These pages are retrieved by a web crawler an automated Web browser which follows every link on the site. The contents of each page are then analyzed to determine how it should be indexed. Data about web pages are stored in an index database for use in later queries. A query can be a single word. The purpose of an index is to allow information to be found as quickly as possible.

For example

Some search engines, such as Google, store all or part of the source page (referred to as a cache) as well as information about the web pages, whereas others, such as Alta vista, store every word of every page they find.

This cached page always holds the actual search text since it is the one that was actually indexed, so it can be very useful when the content of the current page has been updated and the search terms are no longer in it.

Screen Saver

Malik Mudasir Maqbool

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.

Before the advent of LCD screens, most computer screens were based on cathode ray tubes (CRTs). When the same image is displayed on a CRT screen for long periods of time, the properties of the exposed areas of phosphor coating on the inside of the screen gradually and permanently change, eventually leading to a darkened shadow or “ghost” image on the screen. Cathode ray televisions, oscilloscopes and other devices that use CRTs are all susceptible to phosphor burn-in, as are plasma displays to some extent.

Disk Defragmenter

Malik Mudasir Maqbool

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

The Disk Defragmenter in Windows 2000 was a stripped-down licensed version of Diskeeper, licensed from Diskeeper Corporation. It uses the following techniques:^[1]

1. Moving all the index or directory information to one spot. Moving this spot into the center of the data, i.e. one third of the way in, so that average head travel to data is halved compared to having directory information at the front.
2. Moving infrequently used files further from the directory area.
3. Obeying a user-provided table of file descriptions to emphasize or ignore.
4. Making files contiguous so that they can be read without unnecessary seeking.

Diagnostic Utility

Malik Mudasir Maqbool

A diagnostic program is a program written for the express purpose of locating problems with the software, hardware, or any combination thereof in a system, or a network of systems. Preferably, diagnostic programs provide solutions to the user to solve issues.

• Diagnostics that are run on-demand when a user needs assistance, typically within the primary operating system of the computer (e.g. Linux, Windows)
• “Off-line diagnostics” that are run outside the primary operating system, typically to reduce the masking influence of software on hardware issues
• Background diagnostics that monitor the system for failures and marginal events, and provide statistical data for failure prediction, and root cause analysis of actual failure conditions

Disk Scanners

Malik Mudasir Maqbool

According to PC Guide, a disk scanner is a utility installed on a computer system to read for errors in order to optimize the performance of the system. This means it corrects errors that are preventing your programs from running properly. Disk scanners clear out most junk files such as temporary Internet files and files you choose to delete from your computer. Basically, a disk scanner boosts your system’s memory, in order to prevent it from overloading while operating.

Read more: What Are Disk Scanners? | eHow.com http://www.ehow.com/about_5575090_disk-scanners.html#ixzz2SIFjOXGT

Image viewer

Malik Mudasir Maqbool

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.

mage 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.