The World Wide Web, or just the Web, is the most popular part of the Internet by far. Once you spend time on the Web you will realize that there is no limit to what you can discover. The Web allows rich and diverse communication by enabling you to access and interact with text, graphics, animation, photos, audio, and video.
Speaking the Same Language
The World Wide Web, or just the Web, is the most popular part of the Internet by far.
Although the terms are often used interchangeably, the Internet, and the Web are not the same thing. The Internet is a physical network of computer networks scattered all over the world. The Internet is the network that allows two computers on opposite sides of the world to exchange information. However, in order for two computers to exchange information over the Internet, they need to be communicating in the same way or using the same communication protocol. Communication protocols are where the Web comes in. The Web is the portion of the Internet that uses HTTP, or HyperText Transfer Protocol, to transfer information.
There are many other protocols used to transfer information over the Internet that isn't part of the Web. Some of which you probably use on a daily basis. Here are three of the most popular protocols other than HTTP:
- SMTP: Simple Mail Transfer Protocol is the most common email protocol.
- FTP: File Transfer Protocol is the protocol used to transfer files to and from web servers.
- SSL: Secure Sockets Layer is a protocol used to transmit sensitive data in encrypted format rendering the data unintelligible in the event that the transmission is intercepted.
What is the Web?
So just what is the Web? On the simplest level, the Web consists of five things:
- A client: The computer or mobile device used to access the Internet.
- An application: Software used to access the Web, such as a web browser or an app on your smartphone.
- An ISP: A connection to the Internet through an Internet Service Provider.
- A server: The computer where the information being accessed is hosted.
- A network: Routers and switches that direct the flow of information between the client device and the server.
The Web is sometimes referred to as a client-server system. Your computer is the client, and the remote computers that store electronic files are the servers. The Internet connects the client and the server so that they can communicate, and the result is your experience on the Web.
Navigating the Web
Let's say you want to access the Louvre museum website. First, you enter the address or URL of the website in your web browser. Then your browser requests all the data files that comprise the web page from the web server that hosts the Louvre's site. The server transmits the data over the Internet to your computer. Your web browser interprets and assembles the data, displaying it on your computer screen.
The Web is the portion of the Internet that uses HTTP, or HyperText Transfer Protocol, to transfer information.
The Louvre's website also has links to the sites of other museums, such as the Vatican Museum. If you click the link, you access the web server for the Vatican Museum. In this way, information scattered all across the globe is linked together.
The “glue” that holds the Web together is called hypertext and hyperlinks. This feature allows electronic files on the Web to be linked so you can jump easily between them. On the Web, you navigate, commonly known as browsing or surfing, through information based on your interest at that particular moment.
Finding Information on the Web
If you don’t have a particular destination in mind when you access the Internet, or if you are looking for information that you aren’t sure where to find, you will undoubtedly use a search engine to find what you’re looking for.
The three most popular search engines are Google, Bing, and Yahoo!. While each ranks websites a little differently and offers slightly different search capabilities, all search engines function in a similar way.
A search engine is a program that compares search terms to an index of Web content. It does this in three steps:
- First, the search engine sends out programs called spiders or web crawlers, which are written to track down web pages and send the web page content back to a database.
- A second program, called an indexer, reads the information sent back by the spiders and adds it to a massive index of web page content.
- Third, when a search term is entered, the search engine pulls relevant content from the index, sorts it to provide the most relevant information first, and then sends back a list of results.
Every search engine is built with a proprietary algorithm that categorizes and sorts web pages differently. This is why the search results from Google will not be exactly the same as the search results from Bing, even if identical search terms are entered. So if you’re looking for information with one search engine, and you can’t find it, it’s always worth giving the second engine a try.
The Applications that Make the Web Work
To access the Web you need a web browser, such as Internet Explorer, Edge, Firefox, Chrome, or Safari. How does your web browser distinguish between the different types of data on a webpage and decide how to render that information? The answer lies in the files that comprise a webpage.
When your browser is served is a web page from a server it receives three types of files:
- HTML files: Hypertext Markup Language (HTML) files are used to deliver content. They contain the text, links, and references to the media that make up the content of the web page.
- CSS files: Cascading Style Sheet (CSS) files provide formatting for the HTML content. CSS files tell the browser how to present the content in the HTML files.
- Media files: Images, videos, and audio files.
HTML consists of wide variety of elements used to tell the browser the meaning of the content that is being viewed. For instance, in HTML, all paragraph are tagged with a paragraph tag that looks like this:
<p>Paragraph Content</p> There are also tags for headers, tables, form fields, lists, images, videos, and much more. All of these tags tell the browser that the information contained within the tags is one certain kind of information and not another.
On the simplest level, the Web consists of five things: a client, an application, an ISP, a server, and a network.
HTML is also used to serve up media files. So if your page contains a variety of images, a video, and an audio file, HTML tags are used to tell the browser where those media files are located on the server, and what position on the page they should occupy relative to the rest of the information on the page.
While HTML is used to define and deliver content and media, CSS is used to format the content. It dictates things like image size, font style, background color, and the spacing between different HTML elements. CSS files tell the browser what the website should look like, and adapt the website to a variety of device viewport sizes.
The Web is the portion of the Internet that uses the HTTP communication protocol to transfer information between a client, such as a computer or mobile device, and a web server. However, that dry definition doesn’t do justice to the reality of what the Web is. The Web is where information about any topic is just a few keystrokes away. So whether you want to be informed, entertained, or educated, you’ll find the content you seek on the Web.
Understanding Web Addresses
Think of the World Wide Web as a vast collection of electronic files stored on millions of computers all around the world. Hypertext links these files together. Uniform Resource Locators or URLs are the addresses used to locate the files.
The information contained in a URL gives you the ability to hop from one web page to another with just a click of the mouse. When you type a URL into your browser or click a hypertext link, your browser sends a request to a remote computer, called a web server, to download one or more files. Every URL is unique, identifying one specific file.
What does a typical URL look like? Here are a few examples:
- The home page of Website Builders.
- A directory of files at MIT available for downloading.
- A blog about soccer from the Reuters news service.
Let's deconstruct a nasty looking web address:
The first part of a URL (before the two slashes) is called the protocol. It tells the browser the type of resource or method of access at that address. For example:
- hypertext document or directory
- a file available for downloading or a directory of these files
- a file located on a local drive of your computer
In our example, the protocol is “HTTP.”
You will often see another protocol, “https.” This is a kind of secure and encrypted HTTP protocol. It was originally designed for things like credit card processing. But it is used much more widely than that today. Wikipedia uses https for three reasons:
- It provides protection against eavesdropping.
- It has better error detection for people with bad internet connections.
- It stops internet access points from injecting banner ads.
The Web page
The second part is the address of the website where the data or service is located. In our example, the website is Gibberish.com. Often, the web address ends there. Your browser knows to take you to the homepage of the website. But usually, it's a bit more complicated than that.
After the website comes the location of the file on the website. And in many cases, this file is many directories (or folders) deep. In our example, the file unreadable.php is in the almost directory in the base directory of the site: /almost/unreadable.php.
Query Strings and Hashtags
Now we get to the fun stuff that makes webpage addresses look really weird — like the digital equivalent of witchcraft. Some of it is important to you, but most of it is just internal stuff. The question mark signals to the browser that the webpage has been determined by the stuff that went before. After it comes the query strings. These are usually things like “x=something” and they are separated by the ampersand (&) character. Sometimes there are dozens of them.
Most modern browsers will allow you to enter a URL or search terms in the address bar.
Finally, the hashtag (#) just tells the webpage where to position itself. It is most often used when only part of a page is displayed (like on the front page of a blog where the beginnings of a number of articles are listed). When the user clicks a link like “Read more” a new page loads and positions itself to where you left off reading. If you click this link it will take you to the “Details of Web Addresses” section above. Look at how the web address changes.
Using Web Addresses
You enter the URL of a site or webpage by typing it into the address bar of your web browser. But be careful! New browsers also allow you to enter search terms into the address bar. The browsers are pretty good at figuring out what you are trying to do. But sometimes they mess up. Don't let it confuse you.
Browsers can store the URLs you want to revisit by adding them to a special list. Chrome, Firefox, and Safari all call them Bookmarks; Internet Explorer calls them Favorites. Once you add a URL to your list, you can return to that web page by clicking the name on the list, instead of retyping the address — a good thing, as some URLs can be quite long.
Most of the URLs you will use start with HTTP, which stands for Hypertext Transfer Protocol, the method by which HTML files are transferred over the Web. In fact, they are so common, that browsers just assume that you mean it when you don't use anything. So entering “Gibberish.com” is the same as entering “http://www.Gibberish.com.” Here are few other things to know about URLs:
- A URL usually has no spaces. (When it does, it uses the computer code for a space character, “%20.”
- A URL always uses forward slashes (//).
- URLs are case sensitive, but protocols and website names are not. So typing “http://www.Gibberish.com” or “HTTP://WWW.GIBBERISH.COM” or any variation of upper and lower case letters takes you to the same website. But the following will almost certainly fail to load the page you want:
- If you type a URL incorrectly, your browser will not be able to locate the site or resource you want. Should you get an error message or access the wrong site, check to see if you spelled the address correctly.
- You can find the URL behind any hyperlink by placing your cursor over the link. The URL appears in your browser's status bar, usually located at the bottom of your browser window.
- It is often convenient to open a link in a new tab or window. You can do this by right-clicking on the link. This will cause a menu to appear and you can select what you want to do from it.
To learn more about URLs, read the World Wide Web Consortium's Fact Sheet on URLs.