Binary Search is one of the most powerful techniques that exist that can solve a variety of problems of even the highest difficulty. It is highly recommended that you truly understand the core concept behind Binary Search by reading the following tutorials:
Ternary Search is an extension of Binary Search that allows you to locate minima/maxima for Unimodal Functions.
Here are some links to practice Binary Search problems:
Here are some links to practice Ternary Search problems: