Key Server Side Concepts for Client Side Developers
As Client Side developers, we mainly write code that manipulates SharePoint objects at the Site Collection level and below.
The most commonly used objects in the SharePoint Server Side Object Model are:
SPSite and SPWeb for Site Collections and Subsites respectively.
SPList and SPDocumentLibrary for working with Lists and Document Libraries.
SPListItem and SPFile for List Items and individual Files.
SPFolder for Folders.
SPField for Columns and Site Columns, and SPContentType for ContentTypes.
The Client Side Object Model equivalent for all of these has the same name but is not prefixed with the letters SP.