I'm sorry, I didn't know where to put this.

Any HTML coding I've ever done has been on free webpages, I'm now starting an online store and am coming across a whole array of web language I've never even heard before. PHP, web server etc... I don't really understand what a webserver is and why I need it to write a website, especially one involving a shopping cart. Do I use a webs erver to write the code and then transfer it to a web hoster? If someone could please help me that would be great. I am so confused I don't know what to do. Thanks!!