LISP is a programming language that was created in the late 1950s, making it one of the oldest languages still in use today. It is known for its unique syntax, which uses lots of parentheses to structure code. LISP is particularly popular in the field of artificial intelligence because it allows for easy manipulation of symbols and lists, making it great for complex problem-solving. One of the key features of LISP is its ability to treat code as data, which means you can write programs that modify themselves. This flexibility has led to the development of various dialects, such as Common LISP and Scheme, each with its own strengths and uses in different programming tasks.