These are all of the pieces that we'll use to build the puzzle that you'll call your website.

HTML - This is your site's skeleton. Without HTML, you don't have a webpage. It's that simple.
PHP - An open-source, server-side scripting language. Open source means that it's free for everyone to use and for everyone to contribute to. Server-side scripting runs on the web server before the page is ever loaded into the browser. That's how dynamic content is created.
ASP - Microsoft's version of server-side script.
ActionScript - Another scripting language. This one is primarily used to script Flash (or SWF) files to make them more robust and dynamic.
MySQL - SQL (or sequal) is a database language. It is used in conjunction with server-side scripting language to interact with databases to retrieve and also save data. MySQL is the open-source version
Microsoft SQL - Microsoft's version
Flash - Software used to add animation and interactivity to web pages. Flash can do some amazing stuff!
Photoshop - The industry standard for image manipulation. Everybody's seen a Photoshop image somewhere - they just may not have known it!
Dreamweaver - Adobe's web-creation software. It's where we put all of the various components together (html, php, sql, swf) to make your website come to life.
Illustrator - This is a vector graphics application used for creating artwork, logos etc. Vector images are completely scaleable and don't lose resolution.