The Nintendo Game Boy Advance SP is a redesign of Nintendo's original Game Boy Advance handheld game console.
The major changes in this version of the hardware are the reduced size and weight of the system, the change to a clamshell design and the addition of a rechargeable battery and built-in screen light. The screen light is an absolute godsend in this system: almost everyone who played the original GBA complained of the darkness of the screen. The GBA elegantly solves this problem, although the light does drain the battery more quickly.
The major drawback of this design is lack of a headphone port. The port is an odd omission, you have to buy an adapter. Despite this flaw, the GBA is an excellent handheld with a massive library of games, especially now that the proce has come down with the release of the DS.