A URL is an address for a web site, such as www.woodswebdesign.com, but it can also be a very specific address, such as the address of a single page, such as woodswebdesign.com/next/node/4/.
The letters URL are an abbreviation of "uniform resource locator" --aren't you glad we don't have to use that phrase every day?
SMTP is the abbreviation for "simple mail transfer protocol" - the way servers send email messages.
POP is the acronym for "post office protocol" - one of several different ways email programs receive new email messages from mail servers. Most email programs today use POP3, but most people leave the "3" off when talking about their email setup.
FTP is the abbreviation for file transfer protocol, a method for transferring computer files from one computer to another. Typically, FTP is used to transfer files between a desktop computer and a server, such as a web server.
CMS is an abbreviation for "content management system" - which is how most web sites are built these days.
A content management system is a computer software program for creating and organizing a collaborative set of documents and other content. A content management system is usually a web-based application used for managing websites and web content, though in some cases, content management systems require special client software for editing and constructing articles.
HTML is the abbreviation for "hyper text markup language" - which is how web pages can display text, images, colors, backgrounds, etc., with standard HTML "tags" that are interpreted by web browser applications (e.g., FireFox, Internet Explorer, etc.) to display the page as the page's author intended.
The markup part of the phrase refers to how plain text is modified by the tags that surround it.
HTTP is the abbreviation for "hyper text transfer protocol" - which is the way the majority of web-based pages are displayed in web browsers.
The hyper text part of the phrase refers to how HTML (which stands for "hyper text markup language") is used to transfer coded files to web browsers, which then interpret the code and display the page in the format intended by the pages's author.