Binary logarithms or log2 n is the power to which the number 2 must be raised to obtain value n. Binary logarithm (and others) has numerous applications in computer science. Let's take analysis of algorithms for example. All algorithms have a running time, also called time complexity of algorithms.
An algorithm's running time is measured against size of the input. When an algorithm's running time increases in exponential proportion to the input size it is exponential time. This can be represented as O (cn) using Big-O notation. But when dealing with algorithms where time complexity decreases with each iteration by a factor of any given number, representation becomes difficult. This is where