An algorithm, in computer sciences, is a set of rules used for a step by step calculation or optimization. An algorithm is characterized by entry data, instructions and a result.
Algorithm objectives are to achieve the good or best result, but also to save computing ressources and to reduce treatment delays.
In digital marketing context, the best known is Google Algorithm.
Algorithms are increasingly used in digital marketing due to:
automation marketing applications
need of speed and even real time
They are used for ad optimization, emerchandising, sponsored links, etc.