It's been 15 years since Xdebug first came out. We think this is the perfect opportunity to re-introduce it to the world, and explain how and why it does what it does.
Xdebug is a PHP extension (meaning it needs to be compiled and installed into a PHP installation) which provides the developer with some features for debugging. They include:
var_dumpoutput which produces color coded information and structured views, similar to VarDumper, along with a a super-globals dumper