what is algorithm method? where is it used ?

Algorithm are step wise instructions to solve a given problem.

 An algorithm is widely used in   mathematics  , computing and related subjects  . It is basically a sequence of finite   instructions   that are used for calculations and data processing. It is an effective method where a list of well defined   instructions   are used for completing a task.  

 When an initial state is given, an algorithm proceeds through a series of successive states that eventually terminates at the end state. The transition is normally deterministic in nature