iPhone: What is Springboard? Do I need to care?

When creating iPhone apps in simulator, I sometimes see messages like "Springboard failed to launch application", etc.

What is Springboard? Are there things I should know about it as a developer?

From stackoverflow

• Springboard is just the iPhone home screen application.

  This related question may help.

• Springboard is the launcher application -- i.e. the one you see on the home screen with all the tiled app icons.

  I don't think there's anything more you really need to know about it.

• Springboard is the iPhone emulator that your app runs within. If Springboard only periodically fails to launch your app, something's probably wrong with Springboard, but if your app won't launch at all, there's probably something wrong with your app (and if it was deployed on a real phone, wouldn't launch there, either).