What is the Difference between a Web Application and Site Collection

WebApp vs Site collection.  This is a confusing issue:

• Basically a WebApp is a container for sites. 
• Each Web Application must contain at least one Site Collection.
• Each Site Collection can contain more than one site
• A site is usually shown as a tab in a Sharepoint page.

This applies equally to Sharepoint, WSS (Windows Sharepoint Services), Sharepoint 2007, MOSS, Sharepoint Foundation 2010, and Sharepoint Server 2010.

I found a great little table on THIS site which explains it well and it goes a little something like this:

1. Web Application

1.1 Site Collection (SPSite)

1.1.1 Site (SPWeb)

1.1.2 Site (SPWeb)

1.2 Site Collection (SPSite)

1.2.1 Site (SPWeb)

1.2.1.1 Sub Site (SPWeb)

1.2.1.2 Sub Site (SPWeb)

I am a Sharepoint 2010 novice but I have spent considerable time banging through 2010 in recent days and below is information I will need in the future to perform installs at other client sites.  Perhaps you will be interested in some of this.  If you want more of my tips and tricks just type SHAREPOINT in the search, you will find a 3 or 4 more posts from today.