Contemporary worship music is a loosely defined genre of Christian music used in contemporary worship. It has developed over the past sixty years and is stylistically similar to pop music. The songs are frequently referred to as "praise songs" or "worship songs" and are typically led by a "worship band" or "praise team", with either a guitarist or pianist leading. It is becoming a common genre of music sung in Western churches, particularly in Pentecostal churches, both denominational and nondenominational. Also many non Charismatic Protestant Churches use this type of music. Some do so exclusively. Others have services that are just traditional along with services that are just contemporary. Others simply mix this type of music in with traditional. Some Protestant churches avoid this music and remain traditional. Also, Roman Catholic churches are using this type of music in some parishes. Some mix it in with more traditional music; others have certain masses with just contemporary worship music along with traditional masses; others only use contemporary; many others steer clear of contemporary worship and stick with traditional. The type of music used in such churches both Catholic and Protestant has little bearing on theological ideology or whether a church is liberal, moderate, or conservative.