WotLK A question regarding prayer of healing in raids

[LordMitico]

as the topic states, prayer of healing as AoE healing is very questionable for me specially in raids I don't have a clue about what targets it heals (currently thinking it only affects my own group only and I can't really see the effectiveness of it)

can someone please increase my knowledge about this strong AoE heal and when can I actually use it effectively in raids..

thanks for reading

[Mercy]

It heals everyone in the same group as your target within range (range varies on talents). You can target people in other groups with it in WotLK. As such, it is a very powerful tool.

[LordMitico]

It heals everyone in the same group as your target within range (range varies on talents). You can target people in other groups with it in WotLK. As such, it is a very powerful tool.

thanks for pointing that out, it helps alot