The Rabin-Karp algorithm is a string-searching technique used to find a pattern within a text efficiently. It employs hashing to compare the pattern and substrings of the text, allowing for quick checks of potential matches. If the hash values match, a direct comparison is made to confirm the match, reducing unnecessary checks. This algorithm is particularly useful for searching multiple patterns simultaneously. By using a rolling hash function, it can update the hash value of the text as it moves through the string, making it faster than naive search methods. Its average-case performance is generally better than other algorithms for large texts.