Common Lisp Programming Language

Common Lisp is a general-purpose, multi-paradigm programming language that evolved from Lisp, designed for rapid prototyping, symbolic computation, and application development. Standardized as ANSI INCITS 226-1994, Common Lisp represents decades of language evolution from the original Lisp (1958) through Maclisp, Interlisp, ZetaLisp, and Scheme influences. Key features: dynamic and interactive development environment with a read-eval-print loop (REPL) enabling live code modification and incremental development without restarts. CLOS (Common Lisp Object System) providing a powerful multiple-dispatch object system with multiple inheritance, generic functions, method combination, and metaobject protocol for extending the object system itself. Macros enabling code generation and language extension at compile time, allowing developers to create new control structures and domain-specific languages. First-class functions, closures, and lexical scoping with optional dynamic scoping for backward compatibility. Condition system with restarts for structured error handling and recovery, more expressive than traditional exception systems. Garbage collection and automatic memory management. Arbitrary-precision integers and rational numbers. Compiler available at runtime enabling incremental compilation and dynamic code loading. Multiple implementations available including SBCL (Steel Bank Common Lisp, high performance with native compilation), CCL (Clozure CL), CLISP, ECL (Embeddable Common Lisp), ABCL (Armed Bear Common Lisp for JVM), and CLASP (LLVM-based). Quicklisp package manager for installing libraries. ASDF build system. Web frameworks (Clack, Caveman2, Hunchentoot), game engines, and scientific computing libraries. Used in AI research (GRAMMY-winning software), scheduling systems (at Google, NASA, and Naughty Dog), and web applications.