Which house system is used?

We use the Placidus house system. This is the most commonly used house system in modern western astrology. It is based on a division of time, not place. The time required for each degree of the ecliptic to rise from the nadir (IC) to the ascendant, and from the ascendant to the midheaven (MC), is risked to reach the cusps of houses 2, 3, 11 and 12. determine. The cusps of houses 8, 9, 5 and 6 are opposite.

The Placidus system was first mentioned in Arabic texts around the 13th century, but the first publication dates from 1602 and is by Giovanni Antonii Magini (1555-1617) with his book "Tabulae Primi Mobilis, quas Directionem Vulgo Dicunt" .