What do you know about Archaebacteria?

Archaebacteria live in most harsh habitats and named accordingly:

(a) Halophiles - live in extreme salty area

(b) Thermo-acidophiles - live in hot springs.

(c) Methanogens - live in marshy places and guts of ruminant animals such as cows and produce the gas methane.

Archaebacteria have a different cell wall structure from other bacteria.