FLAC is the audiophile's handshake: CD-perfect sound at roughly half the shelf space. It was born in 2001, Josh Coalson; now kept by the open Xiph.Org Foundation, and its real weak spot is fitting in pockets: lossless is still large: and charming Apple's own apps.
WMA is Windows' old house band: big in the early 2000s, mostly retired now. Windows Media Audio, in several variants including a rarely-sighted lossless one. That makes it the right destination when what you need is keeping aging Windows Media software and old archives happy.