As described by the documentation:

Any time you do linear searching, your search time will suffer the further into the list the item occurs. You would see a tremendous benefit if you sorted the list first, and then used a different search technique. BinarySearch is already implemented by the Framework; other search techniques most likely require you to create your own implementation. If you are familiar with "big-O" notation, then a binary search will have O(log(n)) search time. In other words:

The blue line represents a linear search, and the green line represents a binary search. As you can see, as the number of items increases (the X axis), the time to search (the Y axis) grows slower with a binary search.

This method performs a linear search; therefore, this method is an O(n) operation, where n is Count.

Any time you do linear searching, your search time will suffer the further into the list the item occurs. You would see a tremendous benefit if you sorted the list first, and then used a different search technique. BinarySearch is already implemented by the Framework; other search techniques most likely require you to create your own implementation. If you are familiar with "big-O" notation, then a binary search will have O(log(n)) search time. In other words:

The blue line represents a linear search, and the green line represents a binary search. As you can see, as the number of items increases (the X axis), the time to search (the Y axis) grows slower with a binary search.