ASP.NET - Absolute and Sliding expiration in .NET

Absolute and sliding expiration are two Time based expiration strategies.
Absolute Expiration: Cache in this case expires at a fixed specified date or time.
Example: Cache. Insert("ABC", ds, null, DateTime.Now.AddMinutes(1), Cache.NoSlidingExpiration);
The cache is set to expire exactly two minutes after the user has retrieved the data.

Sliding Expiration: the cache duration increases in this case by the specified sliding expiration value every time the page is requested. More a page is requested it will remain in cache, whereas a less requested page will not remain in cache