Central Administration: This is the SharePoint site where you can access administration information like permissions, an Administrator Tasks list and a farm topology. Not all users have access to Central Administration, usually just administrators and managers. Central Administration has three pages: Home, Operations and Application Management.
The Home page features a quick view of what needs to be completed in the Administrator Tasks list as well as other information.
The Operations page lets you determine settings that impact the entire farm. You set up e-mail here.
The Application Management page is where you set up and monitor Web Applications and site collections.
Global Assembly Cache (GAC): The GAC is a folder on the server that's hosting SharePoint. .NET assemblies (.exe and .dll) are stored here for Web Parts and services.
Load balancing URL: This is the domain name for sites that users access in the SharePoint Web Application, or what all of your links on your SharePoint server are prefixed with. For example, when I named the SharePoint site on my virtual PC, I named it "katievpc," so all of my links in SharePoint on my virtual PC begin with http://katievpc. Which is unfortunate because everyone else named their load balancing URLs "moss," like http://susanmoss. Sigh. Another misstep for me.
Out of the box: This just means that a software product or program hasn't been customized or enhanced; it's being used just with whatever features the product came with.
SMTP, or Simple Mail Transfer Protocol: The standard protocol for e-mail on the Internet. It determines the format of the message and the message transfer agent. The message transfer agent stores and forwards the e-mails. Your e-mail client "talks" to the SMTP server to get e-mail from one place to another. You have to set up the SMTP in SharePoint so you can use SharePoint to e-mail people.
Timer job: Some applications need timer jobs to run and perform specific tasks. You can also create your own timer jobs to do scheduled tasks in the Central Administration site by clicking Operations and then Timer Job Definitions.
UAC, or User Account Control: Available on Windows Vista and Windows Server 2008, the UAC manages user accounts. It lets users run their computers as regular users instead of administrators, which is a good thing because computers are more secure if they are running with fewer privileges. An example of UAC is when you see a popup box that reads, "Do you want to allow the following program to make changes to this computer?" after you click on an application