Equal house system
In an equal House System, all houses are 30 degrees in width. The Ascendant degree forms the cusp of the first house, and each subsequent house begins at the same degree. Although the Descendant will also form the 7th house cusp, the Medium Coeli (midheaven or MC) and Imum Coeli (IC) are usually embedded within a house; usually but not necessarily the 10th and 4th houses, respectively.
The whole sign system is another type of equal house system, in which the ascendant sign, not the degree, determines the start of the first house, which is always set at 0 degrees of the sign. Each sign follows in order, and is always 30 degreees in width. The angles are typically embedded within a particular house and sign. The whole sign system was probably the one most commonly used in Antiquity and today has a following among Hellenistic and other western traditional astrologers. It is the main house system used in Vedic astrology.