// STRICT MODE
"user strict";	// put at the beginning of script or inside a function

throws errors when...

• variables are not being initialized properly
• trying to assigne value to a non-writable property (instead of ignoring it!)
• trying to delete objects that are not created (instead of ignoring it)
• function "myFunc(a,a,b)" is not allowed! -> without strict mode it will be ignored!
• "with" and "eval" something.. (dont know yet)