The denomination Proto Prog comes from the combination of two words, Proto from the Greek The earliest,. and Prog which as we know is a short term for Progressive Rock, so as it's name clearly indicates, refers to the earliest form of Progressive Rock or Progressive Rock in embryonary state.

These bands normally were formed and released albums before Progressive Rock had completely developed (there are some rare Proto Prog bands from the early 70's, because the genre hadn't expanded to all the Continents simultaneously)

The common elements in all these bands is that they developed one or more elements of progressive rock, and even when not completely defined as part of the genre, they are without any doubt, an important stage in the evolution of Progressive Rock.

Generally, Proto Prog bands are the direct link between Psyche and Prog and for that reason the Psychedelic components are present in the vast majority of them, but being that Progressive Rock was born from the blending of different genres, we have broadened the definition to cover any band that combined some elements of Progressive Rock with other genres prior to 1970.

Some of these bands evolved and turned into 100% Prog, while others simply chose another path, but their importance and contribution in the formative period of Prog can't be denied, for that reason no Prog site can ignore them.