Memory Management

Hi,
I want to know how we will manage memory while programing web applications and how to know if there is a memory leak.
I have an application which gets data from a view available in sql server and refreshes the grid every 2 secs using Ajax UpdatePanel. This page runs all the time in the client machine.
How can I check whether the memory is used properly when its run all the time and doesn't cause any memory leak problem or any system crash.
 
Thanks in advance.
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