What is the IDE for Ruby?

Question

ruby

I got interested, I started to study Ruby, I read a book, while the examples were simple irb was enough, but now the code is already in several files, and in general I want convenience (I’m used to intellisense anyway), I downloaded IronRuby it became better (I still didn’t understand about intellisense, either it’s not there, or it doesn’t work for me), but it’s still somehow inconvenient, there must be something more convenient.
Is there a default IDE for Ruby?
What IDE do you (Ruby developers) use?

Answer 1

RubyMine

Answer 2

Aptana RadRails (http://www.aptana.com/products/radrails)

Answer 3

TextMate.

Answer 4

RubyMine

Answer 5

NetBeans

Answer 6

Here: https://github.com/dreikanter/ruby-bookmarks highlights three IDEs:
Sublime Text
RubyMine
Atom

Answer 7

Ruby for NetBeans :
deadlock.netbeans.org/hudson/job/ruby