Editing Declarative programming (section)

===Logic programming===
{{main|Logic programming}}
Logic programming languages, such as [[Prolog]], [[Datalog]] and [[answer set programming]], compute by proving that a goal is a logical consequence of the program, or by showing that the goal is true in a model defined by the program. Prolog computes by reducing goals to subgoals, top-down using [[backward chaining |backward reasoning]], whereas most Datalog systems compute bottom-up using [[forward chaining |forward reasoning]]. Answer set programs typically use [[Boolean SAT solver |SAT solvers]] to generate a model of the program.