ruby - What does "$>" represent in Ruby documentation?

Question

As in:

def PP.pp(obj, out=$>, width=79)
...

This is from the pp method of the PP class:
http://www.ruby-doc.org/stdlib-2.0/libdoc/pp/rdoc/PP.html#method-c-pp

Answer 1

$>是 Kernel#print（因此是puts）和其他输出方法的 IO 目标。它默认为 $stdout，但可以更改以更改print、printf、puts等的行为。