Clojure is a programming language that is a dialect of the Lisp programming language. It is a general-purpose language that emphasizes functional programming and immutability. Clojure runs on the Java Virtual Machine (JVM) and provides seamless interoperability with Java code. It is designed to be a practical and efficient language for building large-scale, concurrent, and distributed systems. Clojure is known for its simplicity, expressiveness, and powerful abstractions for managing state and concurrency.