what is the difference between Hill climbing and A*?

Question

In Artificial intelligence, these algprithms are very popular. I tried looking for methods to solve the 8puzzle problem and it seems like both of them have a similar approach. Can anyone explain what is the difference?

Answer 1

Algorithms like weighted A* (Pohl 1970) systematically explore the search space in ’best’ first order. ’Best’ is defined by a node ranking function which typically considers the cost of arriving at a node, g, as well as the estimated cost of reaching a goal from a node, h. Some algorithms, such as A∗ ǫ (Pearl and Kim 1982) also consider the distance of a node from the goal, d. Hill-climbing algorithms are less deliberative; rather than considering all open nodes, they expand the most promising descendant of the most recently expanded node until they encounter a solution.

Source (page 1, Introduction)