How the Internet Came to Be
Science fiction writer William Gibson originated the term “Cyberspace” in the early 1980s. His novel Neuromancer popularized the term, which refers to a virtual world within a computer network. Picture the Matrix movies here. This term is often used as a synonym for the Internet, although it could refer to any technology that takes the user out of the “real world” for any time. As technology has become more pervasive in everyone’s life and we are plugged in all the time, some question the need for a term to distinguish between being online and offline.
The Internet is a means to share information with other people around the world. Most of us think of the Internet as being the World Wide Web (WWW), but it is far more encompassing than that. The WWW is one aspect of the Internet, but it also includes email, newsgroups, Instant Messaging, FTP (File Transfer Protocol), etc. These Internet tools are used to digitally communicate with others using protocols, which tell the various connected devices how to communicate with each other. Protocols and other Open Standards are defined so that anyone developing software can be confident that their product will interoperate with all products that also follow the standards.
The current Internet is a descendant of the ARPANet, which was originally a project started by the Department of Defense in conjunction with UCLA, Stanford, UC Santa Barbara, and the University of Utah. It used a technology called packet-switching, where a message is broken up into many small pieces (or packets), sent through the network, and then reassembled. Many of the basic services we use today, like transferring files and sending messages, were available even back in the 1960s when ARPANet began. Since any kind of communications network is inherently unreliable, the network was designed to be completely redundant. No specific server was in charge, because that would open the network to a single point of failure. All computers on the network were able to communicate with every other computer on the network. More universities and government agencies were added, and it eventually grew to the network we know and use today. It’s impossible to know how large the internet is, since there is no central authority that could measure it, besides the fact that it is growing too fast.
A server is set up to share information, and the computers that access data on the server are called clients. It is possible for clients to act as servers and vice versa. For example, think of the peer-to-peer (P2P) networks made famous by Napster and other file sharing programs. These programs allow you to download files from other users while you are letting others download files from your computer, so your computer is acting as both a client (while downloading) and a server (while others are downloading from you) at the same time. Servers can be accessed by many different types of computers from desktops to video recorders like TiVo to cell phones over a variety of networks.
Browsing the World Wide Web
The World Wide Web consists of web pages stored on servers and accessed by clients. Each web page is coded in a language called HTML (HyperText Mark-up Language), which tells the web browser how to display the content on the page. The client makes an HTTP (HyperText Transfer Protocol) request and the server returns the requested page. HTTP is the protocol, which is why you see it in the address bar. If you have a secure connection, it will show up as HTTPS, which is a different protocol that encrypts your data before sending it across the network. A secure connection simply means that people other than the receiver are not able to read your message if it is intercepted. As you will read in the following pages, you still need to make sure you are communicating with someone you trust.
Some common web browsers used today are Internet Explorer, Firefox, Netscape, and Safari. There are many others. Most browsers are quite similar, but they do have differences that should be considered when looking for one to use. Internet Explorer is the most common, as it comes preinstalled with Windows, but Firefox is a rapidly growing alternative due to its additional features and security. Safari is the most commonly used browser on Macs. In addition to full computer browsers, many PDAs and cell phones now have mini-browsers that allow them to view web pages. It is becoming more common for websites to provide content that is optimized for the small screens and slow internet connections of such devices.
In order to access content through the Internet, an Internet Service Provider (ISP) is required. Some common ISP connections are a dial-up modem, cable, DSL, and wireless. Dial-up used to be the most common way to get online, but it is being replaced very quickly by the high-speed options that are more available now. Cable and DSL allow users to connect through their cable or phone lines. There are several options available for wireless connections, with the most common being 802.11b/g or WiFi, which is often available at stores, restaurants, hotels, airports, and even some city parks, since the necessary hardware is built into almost all laptops.
Downloading a file means to save a file from another computer and store it on the one you are working on. These files can be documents, installers for other programs, plug-ins, etc. Uploading means to transfer a file from the client you are using to a server somewhere else. When downloading files from the Internet, follow the same rules as when opening an email attachment. Choose whether you want to open or save the file, and when you do save it, remember where you put it and what it is named, and the most important rule - only open something you obtained from a trusted source.