What is the difference between linear search and binary search?

The main difference between linear search and binary search lies in the way they search for a target element within a given list or array.

Linear search, also known as sequential search, is a simple search algorithm that checks each element in the list one by one until the target element is found or the end of the list is reached. It starts from the beginning of the list and compares each element with the target element. If a match is found, the search is successful, and the position of the target element is returned. However, if the target element is not present in the list, the search will continue until the end of the list is reached, resulting in a worst-case time complexity of O(n), where n is the number of elements in the list.

On the other hand, binary search is a more efficient search algorithm that requires the list to be sorted in ascending order. It follows a divide-and-conquer approach by repeatedly dividing the search space in half. It starts by comparing the target element with the middle element of the list. If they match, the search is successful, and the position of the target element is returned. If the target element is smaller than the middle element, the search continues in the lower half of the list. If the target element is larger, the search continues in the upper half. This process is repeated until the target element is found or the search space is reduced to zero. Binary search has a worst-case time complexity of O(log n), where n is the number of elements in the list. This makes it significantly faster than linear search for large lists.

In summary, the main differences between linear search and binary search are:
1. Linear search checks each element in the list sequentially, while binary search divides the search space in half.
2. Linear search works on both sorted and unsorted lists, while binary search requires the list to be sorted.
3. Linear search has a worst-case time complexity of O(n), while binary search has a worst-case time complexity of O(log n).
4. Binary search is generally faster than linear search for large lists, but it requires the list to be sorted.