Content class is used to refine the sharepoint search results can be very helpful. Here is an example. Let us suppose that in your organization, many users search for Document Library on a daily basis. However due to common keyword used in many sites, do. your search results are cluttered. So to avoid this, you can use content class to filter out.
The following are the types of Content Class available
- Search Query: urn:content-class:SPSSearchQuery
- News Listing: urn:content-class:SPSListing:News
- People: urn:content-class:SPSPeople
- Category: urn:content-classes:SPSCategory
- Listing: urn:content-classes:SPSListing
- Person Listing: urn:content-classes:SPSPersonListing
- Text Listing: urn:content-classes:SPSTextListing
- Site Listing: urn:content-classes:SPSSiteListing
- Site Registry Listing: urn:content-classes:SPSSiteRegistry
- Site: STS_Web
- List: STS_List
- List Item: STS_ListItem
- Events: STS_List_Events
- Tasks: STS_List_Tasks
- Announcements: STS_List_Announcements
- Discussions: STS_List_DiscussionBoard
- Contacts: STS_List_Contacts
- Links: STS_List_Links
- Document Library: STS_List_DocumentLibrary
- Document Library Items: STS_ListItem_DocumentLibrary
- Picture Library: STS_List_PictureLibrary
- Picture Library Items: STS_ListItem_PictureLibrary
Happy SharePointing :-)