You can only do some things, like installing applications, if you have admin privileges.
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# Problems caused by administrative restrictions

You may experience a few problems if you don't have administrative privileges. Some tasks require admin privileges in order to work, such as:

Connecting to networks or wireless networks

Viewing the contents of a removable disk connected to the computer, or the contents of a different disk partition (e.g. a Windows partition)

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You can change who has admin privileges.