Info Tech Guide

In computer terminology a cookie is information that a Web site puts on your hard disk so that it can remember something about you at a later time. (More technically, it is information for future use that is stored by the server on the client side of a client/server communication.) Typically, a cookie records your preferences when using a particular site. 

Using the Web's Hypertext Transfer Protocol (HTTP), each request for a Web page is independent of all other requests. For this reason, the Web page server has no memory of what pages it has sent to a user previously or anything about your previous visits. A cookie is a mechanism that allows the server to store its own information about a user on the user's own computer.

A Captcha is program used to verify that a human, rather than a computer, is entering data. Captchas are commonly seen at the end of online forms and ask the user to enter text from a distorted image. The text in the image may be wavy, have lines through it, or may be highly irregular, making it nearly impossible for an automated program to recognize it. Some captchas are so distorted that they can be difficult for humans to recognize as well. Fortunately, most captchas allow the user to regenerate the image if the text is too difficult to read. Some even include an auditory pronunciation feature.

By requiring a captcha response, webmasters can prevent automated programs, or "bots," from filling out forms online. This prevents spam from being sent through website forms and ensures that wikis, such as Wikipedia, are only edited by humans. Captchas are also used by websites to make sure users don't bog down the server with repeated requests. While captchas may be a minor inconvenience to the user, they can save webmasters a lot of hassle by fending off automated programs.

CSS stands for "Cascading Style Sheet." Cascading style sheets is designed primarily to enable the separation of document content (written in HTML or a similar markup language) from document presentation, including elements such as the layout, colors, and fonts.This separation can improve content accessibility, provide more flexibility and control in the specification of presentation characteristics, enable multiple pages to share formatting, and reduce complexity and repetition in the structural content (such as by allowing for tableless web design).

CSS can also allow the same markup page to be presented in different styles for different rendering methods, such as on-screen, in print, by voice (when read out by a speech-based browser or screen reader) and on Braille-based, tactile devices. While the author of a document typically links that document to a CSS style sheet, readers can use a different style sheet, perhaps one on their own computer, to override the one the author has specified.

Internet Protocol (IP) is the principal communications protocol used for relaying datagrams or packets across an internetwork using the Internet Protocol Suite. Responsible for routing packets across network boundaries, it is the primary protocol that establishes the Internet. Most networks combine IP with a higher-level protocol called Transmission Control Protocol (TCP), which establishes a virtual connection between a destination and a source.

The Internet Protocol (IP) is the method or protocol by which data is sent from one computer to another on the Internet. Each computer (known as a host) on the Internet has at least one IP address that uniquely identifies it from all other computers on the Internet. When you send or receive data the message gets divided into little chunks called packets.

Uniform Resource Locator (URL) is a Uniform Resource Identifier (URI) that specifies where an identified resource is available and the mechanism for retrieving it. URL is the address of a specific Web site or file on the Internet. It cannot have spaces or certain other characters and uses forward slashes to denote different directories.

The Uniform Resource Locator was created in 1994 by Tim Berners-Lee and the URI working group of the Internet Engineering Task Force. The format is based on Unix file path syntax, where forward slashes are used to separate directory or folder and file or resource names. Conventions already existed where server names could be prepended to complete file paths, preceded by a double-slash (//).

Uniform Resource Identifier (URI) identifies the name and location of a file or resource in a uniform format. It includes a string of characters for the filename and may also contain the path to the directory of the file. URIs provide a standard way for resources to be accessed by other computers across a network or over the World Wide Web.  URIs are similar to URLs in that they specify the location of a file. However, a URI may refer to all or part a URL.

The most common form of URI is the Web page address, which is a particular form or subset of URI called a Uniform Resource Locator (URL). Another kind of URI is the Uniform Resource Name (URN). A URN is a form of URI that has "institutional persistence," which means that its exact location may change from time to time, but some agency will be able to find it. 

HyperText Transfer Protocol (HTTP) is the protocol used to transfer data over the World Wide Web. That's why all Web site addresses begin with "http://". Whenever you type a URL into your browser and hit Enter, your computer sends an HTTP request to the appropriate Web server.

The Web server, which is designed to handle HTTP requests, then sends to you the requested HTML page.HTTP is the set of rules for transferring files (text, graphic images, sound, video, and other multimedia files) on the World Wide Web. As soon as a Web user opens their Web browser, the user is indirectly making use of HTTP. HTTP is an application protocol that runs on top of the TCP/IP suite of protocols.