What is Psychedelic Rock?

Psychedelic Rock emerged in the mid 60’s from the British Invasion scene. With the help of mind-expanding stimulants (or maybe not) the music consisted of simple and almost ludicrous lyrics, coupled with electronic and voice assisted experimentations. The Blues still formed the substrata of this genre.
A few famous Psychedelic Rock bands include early Pink Floyd, Nektar, Porcupine Tree and Eloy.
A few classic Psychedelic Rock albums include
· Pink Floyd’s The Piper at the Gates of Dawn
· Pink Floyd’s Ummagumma
· Pink Floyd’s Saucerful of Secrets
· Porcupine Tree’s The Sky Moves Sideways
· Porcupine Tree’s In Absentia
· Nektar’s Journey to the Center of the Eye
· Eloy – Dawn

What is Progressive Metal or Prog-Metal?

The clamorous progeny of progressive rock, characterized by the use of complex themes and distorted, non-rhythmic time signatures. Band which typically figure in this category include Dream Theater, Tool, Liquid Tension Experiment, Queensryche and Savatage. These bands create tunes inspired by Progressive Rock giants like Pink Floyd and Rush and amalgamate the tunes with influences from Megadeth, Metallica, Black Sabbath and Iron Maiden.
A few classic Prog-Metal albums are:
· Dream Theater’s A Change of Seasons
· Dream Theater’s Scenes from a Memory
· Liquid Tension Experiment’s Liquid Tension Experiment 1
· Savatage’s Gutter Ballet
· Shadow Gallery’s Tyranny
· Queensryche’s Operation Mindcrime
· Tool’s Lateralus

What is Progressive Rock?

Progressive Rock is an affectedly genteel style of rock music, dotted with elements of pomposity and grandeur. The whole Progressive Rock movement was believed to have emerged somewhere around the late 60's in England. It reached the pinnacle of its popularity during the 70's but there are vestiges of this movement even today.
Some of the common features of Progressive Rock are:
1. Concept albums - Pink Floyd's "The Wall", Yes "Close to the Edge", Rush "2112", early Genesis "The Lamb Lies Down on Broadway"
2. Tonnes of electronic and/or simulated sound systems - Pink Floyd, Rush, King Crimson
3. The need to borrow or redefine a classical piece of work - Emerson, Lake and Palmer's "Hoedown" inspired by Aaron Copland's Rodeo, Yes' "Siberian Khatru" inspired by Igor Stravinsky's "Rite of Spring" , Jethro Tull's "Bouree" cover of the original by JS Bach
4. Creating song structures similar to classical suites, i.e., dividing the song into movements - Yes' "Close to the Edge", ELP's "Tarkus", Rush's "Cygnus X/1"