Some Key Terms- Internet and Web Design

1. Define the term - Protocol:When computers communicate with each other, there needs to be a common set of rules and instructions that each computer follows. A specific set of communication rules is called a protocol.
2. What are the following protocols used for?

TCP/IP: Stands for "Transmission Control Protocol/Internet Protocol." These two protocols were developed in the early days of the Internet by the U.S. military. The purpose was to allow computers to communicate over long distance networks. 

http: Stands for "HyperText Transfer Protocol." This 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.

SMTP: Stands for "Simple Mail Transfer Protocol." This is the protocol used for sending e-mail over the Internet. Basically, SMTP is a set of commands that authenticate and direct the transfer of electronic mail.

POP: Stands for "Post Office Protocol." "POP" is a simple, standardized method of delivering e-mail messages. A POP mail server receives e-mails and filters them into the appropriate user folders. 

FTP: Stands for "File Transfer Protocol." It is a common method of transferring files via the Internet from one computer to another. 

3. What does GUI stand for? What was used before GUI? Stands for "Graphical User Interface". It refers to the graphical interface of a computer that allows users to click and drag objects with a mouse instead of entering text at a command line.  The graphical user interface was first introduced to the public by Apple with the Macintosh in 1984. However, the idea was actually taken from an earlier user interface developed by Xerox. Early dynamic information devices such as radar displays, where input devices were used for direct control of computer-created data, set the basis for later improvements of graphical interfaces.

4. There are two methods of data transmission – serial and parallel. Explain the difference between them.

Serial transmits data one bit at a time as it only is connected by one wire whereas parallel transmits anything up to a byte at a time if connected by 8 wires.

5. Define the term “URL”. Explain the components that make up the url.

Stands for "Uniform Resource Locator". A URL is the address of a specific Web site or file on the Internet. A URL is used when a Web client makes a request to a server for a resource. A URL for HTTP (or HTTPS) is normally made up of three or four components:
1. A scheme. The scheme identifies the protocol to be used to access the resource on the Internet. It can be HTTP (without SSL) or HTTPS (with SSL).
2. A host. The host name identifies the host that holds the resource. For example, www.example.com.
   Host names can also be followed by a port number. Well-known port numbers for a service are normally omitted from the URL. Most servers use the well-known port numbers for HTTP and HTTPS , so most HTTP URLs omit the port number.
3. A path. The path identifies the specific resource within the host that the Web client wants to access.
4. A query string. If a query string is used, it follows the path component, and provides a string of information that the resource can use for some purpose (for example, as parameters for a search or as data to be processed). The query string is usually a string of name and value pairs, for example, q=bluebird.

6. In the context of data transmission, what is “error detection”? 
It is simply the searching for an detection of any errors that may have occurred in the sending of data

7. Why would error detection be important for the internet

8. Name and explain one common method of error detection.
The oldest method of error correction involves using parity. It works by adding an additional bit to each character word transmitted. The state of the bit is determined by a number of factors such as the type of parity and the number of logic-one bits in the data character.
 
 


 *A parity bit is a bit that is added to ensure that the number of bits with the value one in a set of bits is even or odd. Parity bits are used as the simplest form of error detecting code.

9. What is HTML and explain why it is important

HTML stands for Hyper Text Markup Language; HTML is not a programming language, it is a markup language. HTML is what formats web pages. It is used in conjunction with JavaScript and CSS to make the page you see. It is used to format the text, layout, images, links, etc. The combination of these three elements has come to be known as XHTML.