Game-Creation Tool <> Scripting/Programming Language
- GameMakerStudio - Drag & drop or GameMakerLanguage
- Ren'py - Python/Similar to Python
- Unity3D (5) - Unity/Javascript & C#
- Stencyl - Drag & drop or Haxe
Simple HTML/JS/CSS Text Editor: Text-Wrangler (one of my favourite, OS X)
Graphics Tools:
- Acorn - OS X
- Paintbrush - OS X
- Gimp - OS X, Linux, Windows
- Paint.Net - Windows
- FL Studio
- Garage Band
- FamiTracker
- BFXR
- Audacity (music editing software)
Tutorials For The Above Engine Languages:
- Unity3D - Unity Learn (on the Unity3D website)
- HTML/JS/CSS - W3-Schools.com
- GameMakerStudio - ShaunSpalding (Youtube Channel)
- Ren'py - Ren'py Website & Maddy E (Youtube Channel)
- Stencyl - Stencyl provides good sources for learning
Please don't be offended if a tool/software/language which you think should be here isn't, these are just a few tools & resources which I'm familiar with which are suited for both beginners & intermediates (and advanced).