A binary search divides a range of ordered values into halves (two equal portions) and continues to split the array until the position of unknown value is found. It is an example of a "divide and conquer" algorithm. One of the common ways to use binary search is to find an unknown item in an array. It has the run-time complexity of O(log n). An array is a container object that holds a fixed number of values of a single type. In Java programming language the length of an array is established when the array is created. But in Javascript, neither the length of a JavaScript array nor the types of its elements are fixed. Python programming language considers arrays as lists that can contain mixed data types. Following paragraphs try to describe the binary search in details. Binary search works with only sorted collections. That is due to the binary search looks for a particular item by comparing the middle element of the array. If it matches the item we look for, the index o