Sharepoint as we know is a Content Management System developed by Microsoft that allows users to share the data (like word documents and stuff) in a web-based collaborative environment.

SharePoint is mostaly used to create Companies Intranet Portal, where people can upload and Share documents they work on.

In brief, SharePoint is Used to perform following functions in a company(Common Ones...)

1. Share Documents( like Word docs, excel sheets or simply some data values).
2. Start a Workflow on Document\Data.
3. Display Companies Announcements ( You are given a template to write and publish announcements on a aspx Page)
4. Display RSS feeds from various sources including SharePoint lists.
5. Display Data from other sources like SQL server, Access and other on companies Intranet Page.
6. Send E-mails (Automatic Alerts) for anything or everything happening in the companies portal.
7. Create aspx Pages and add data to them without writing code.
8. Make the intranet Portal Site Public ( It will behave like any other site on the web.)

a lot more ....

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