Preamble: How the web works

by Sean Stephens

Before you can hope to understand Lasso, you need to start by understanding a little about how the internet works.

For those of you who are truly uninitiated, let me note point number one: the internet is NOT the World Wide Web. The "internet" is a catch-all phrase for a global network of physical devices all connected via similar technical protocols. In theory, any one point of the internet can connect to any other point.

An excellent metaphor for describing "the internet" would be to draw a comparison to roads in North America. In North America, one can start on virtually any road (from one driveway, for example) and make your way to any other road (and thus another driveway), with an appropriate vehicle. Unless you are prevented from getting to a particular road by an additional device (a border, or a gate, for example), you can theoretically get from one address to another without interruption - it is a series of connected connections. Roads, then, could be called an asphaltnet.

The World Wide Web, however, is a very specific set of transportation along these roads, involving the viewing of information from a server by a computer, using a program (aka "client") called a "browser". It is merely a thing using the internet (though one of the most popular - another mechanism which uses the internet, for example, is email).

The "Web", as it were, is comprised of a series of documents (web pages) which are housed on specific computers, connected to the internet. When you go to your computer, open a browser, and request a page (by typing a "URL" into the box at the top), your computer goes out (albeit magically) and engages with a series of different technical devices (routers and DNS servers, blah blah blah) to figure out where the document is held and then go retrieve the document. The browser on your computer then takes the document and uses the code in the document to paint an intended picture on the computer screen.

It's not unlike going to the Library, photocopying a page, bringing it home and reading it. Once you've read that page, you go back to the library and photocopy another one. The web is, however, somewhat faster and more efficient (and less hard on trees).

The very first time you go looking for a document (i.e. call a web page with your browser), your computer goes through an initial search process to find another computer. Your computer would need to find another computers's address, which in the computer world is represented by a numerical address, called an IP address (e.g. 1.2.3.4). Every computer connected to the internet has an IP address, although it may have an address within an address (like a condo number within an apartment building). When you type in an easy-to-remember word-based address (e.g. www.lassosoft.com), your computer first goes to a special computer (a DNS server) and asks for directions to the "real" address, the IP address.

Once your computer has this address, it can request a specific document, i.e. a web page. Every web page is represented by a different "URL". Here are some examples of different documents;

www.lassosoft.com/aboutus
www.lassosoft.com/seanstephens

Your computer, then, is going out over the internet, finding another computer, getting and retrieving and then displaying this document. Every time you interact with a browser by "clicking a link" or "submitting a form", your computer goes and gets another document and displays it for you. This is usually easily marked by a "flash" (called a "redraw" in programmer speak) as the content is painted on your screen.

This is the world wide web - a big library of documents (called web pages) which you can access from any computer in the world at any time. These days, faster that you can say "LassoSoft".

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