# VCL Reference

- [Default Functions](/config/vcl/funciones-por-defecto.md)
- [VCL Objects](/config/vcl/vcl-objects.md)
- [Callable Functions](/config/vcl/callable-functions.md): Subroutines to handle requests
- [Security restrictions](/config/vcl/limitaciones.md)
- [Varnish book](/config/vcl/varnish-book.md)