Assuming you mean just burning recordable CDs at home, and not actually producing retail-standard discs, two of the most popular programs are Nero and Easy Media Creator (formerly called Easy CD Creator and Easy CD & DVD Creator). But since your CD burner will come with some software anyway, there's usually no need to buy it separately - they usually come bundled with one of those two programs. Windows XP also has CD burning facilities built-in, and if you want to make audio CDs you can do it directly from within recent versions of Windows Media Player and RealPlayer.