Sharepoint 2010 recycle bin

Recycle bin allows users to restore the objects that are deleted.Microsoft sharpoint server 2010 supports two stages of recycle bin:
a.The first stage recycle bin 
b.Site collection - the second stage .

When recycle bins are enabled then users can restore items,documents etc.

When a user does this	The item is	The item can be restored by
Deletes an item	Held in the first-stage Recycle Bin until the item is deleted from the Recycle Bin or the item has been in the Recycle Bin longer than the time limit configured for an item to be held in the Recycle Bin.	Users or site collection administrators
Deletes an item from the Recycle   Bin	Held in the second-stage Recycle Bin	Site collection administrators

First Stage Recycle bin: The first stage recycle bin is located at site level and it is available to users who have Contribute, Design or Full Control permission on a site.When a user deletes an item from a Web site, the item is sent to the site's first-stage Recycle Bin. Items located in the first-stage Recycle Bin count toward the site quota.Items remain in one of the first-stage Recycle Bins in the site until a specified time period has been reached (the default setting is 30 days).

Second Stage Recycle Bin: The second stage site collection is located at site collection administrator level.
Items remain in the second-stage Recycle Bin until a specified time period has been reached (the default setting is 30 days) or until the second-stage Recycle Bin reaches its size limit, at which time the oldest items are deleted. The time limit for the Recycle Bins applies to the total time after the item was initially deleted — not the time spent in either Recycle Bin stage.                                           
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