Binary search is a classic algorithm used in computer science to efficiently search for a target value within a sorted array. It works by repeatedly dividing the search interval in half. At each step, the algorithm compares the target value with the middle element of the array. If the target value matches the middle element, the search is successful. If the target value is less than the middle element, the algorithm narrows the search to the lower half of the array; if it is greater, the algorithm narrows the search to the upper half. Binary search has a time complexity of O(log n), making it much faster than linear search algorithms (O(n)). However, it requires the array to be sorted, which can be a limitation in some scenarios. To implement binary search, you need to keep track of the low and high indices of the current search interval and update them accordingly in each iteration. By understanding how binary search works and its time complexity analysis, you can better appreciate its efficiency and applicability in various programming tasks.