Hack is a programming language created by Meta (formerly Facebook) to add static typing to PHP-style development. It runs on HHVM (HipHop Virtual Machine) and blends dynamic and static typing to enable fast iteration without sacrificing code quality.

Hack supports advanced features such as generics, nullable types, and a powerful type checker that provides immediate feedback. The language is designed to be compatible with existing PHP code, making adoption and integration into legacy projects straightforward.

If you know PHP but want stronger type guarantees and modern language features, Hack can be an excellent option - combining PHP’s ease of use with enhanced type safety for more maintainable applications.