Eubacteria and Archaebacteria are two kingdoms that include all bacteria. Bacteria make up the largest number of living things on earth. The distinction between the two bacterial kingdoms has to do with the kind of environment in which they are found.
Archaebacteria Kingdom contains bacteria that live in extreme areas, like the hot, deep sea volcanic vents in the ocean, the Dead Sea (lots of salt), or highly acidic areas.
Eubacteria Kingdom contains common type of bacteria, like the ones that live in your mouth and on surfaces of things like counters and keyboards.
Both of these kingdoms have the following characteristics:
Structure: Single-celled
Cell Type: Prokaryote (many have a cell wall)
Energy Requirements: Some are autotroph and some heterotroph
*Note: Some texts and websites still recognize a five kingdom system. In the five kingdom system there is one bacteria kingdom called Moneran. Because there are so many bacteria, today most scientists separate the Moneran kingdom.