What exactly is a wma song?

WMA stands for Windows Media Audio. Windows Media Audio is one of today's most popular Net audio formats. Though not as popular as MP3, WMA tends to outperform MP3 in the area of sound quality, particularly with files encoded at lower bitrates like 64 or 96 Kbps. This performance advantage makes it handy for applications like portable digital audio players, where total play time is limited by a finite amount of internal memory.