Key classes in the SharePoint object model

Document Libraries (Microsoft.Sharepoint)

SPDocumentLibrary

SPPictureLibrary

Features (Microsoft.Sharepoint)

SPFeatureDefinition

SPElementDefinition

SPFeatureProperty

SPFeatureScope

SPFeature

Sites (Microsoft.SharePoint)

SPSite

SPSiteCollection

SPSiteAdministration

SPWeb

Business Data Catalog (Microsoft.Office.Server.ApplicationRegistry.Administration)

EntityCollection

ApplicationRegistry

Meetings (Microsoft.SharePoint.Meetings)

SPMeeting

MtgUtility

Solutions (Microsoft.SharePoint.Administration)

SPSolution

SPFeatureReceiver

SPSolutionCollection

Lists (Microsoft.SharePoint)

SPList

SPListItem

SPListItemCollection

User Profiles (Microsoft.Office.Server.UserProfiles)

UserProfile

UserProfileManager