A birth chart has 12 houses with each house dealing with a different aspect of one's life. A simple analogy is would be the different ministries in a government.
Depending on the zodiac sign placed in each house, different planets will have a different ministries if you will.
For example in a chart with aries as the ascendant,Mars by its virtue of being the lord of Aries will be the lord of the first house. Simillaely sun will be the lord of the 5th house as leo will be in the 5th house. I am going to explain the various houses and what each house represents below. But before that i want to talk about how these houses relate with the sky as we can see it.
The 1st house is at the east horizon and the 7th house is at the west horizon. So when the sun rises, it is in the 1st house, as the day moves on it goes to the 12th house --> 11th house --> at noon it is in the 10th house --> 9th house --> 8th house --> 7th house and sets below the west horizon, and in the night sun moves 7 --> 6 --> 5 --> 4 -->3 --> 2 -->1 (sun rise again). All the zodiac signs and garaha move in a clockwise direction with refrence to a birth chart.
The first is also called the ascendant. It represents the self. The appearance, physique, intellect, vigour, joy and hapiness. A weak ascendant means a weak prime minister and a weak government by its extension. It is the "I" of the birth chart.
This house deals with the wealth (not income), house and speech.
This house deals with brothers, sisters, friends, valour.
This house deals with mother, home, land, cars, vehicles.
This house deals with sons, education, luck, managerial skills.
This is the house of the enemies, litigations, diseases, maternal uncles.
This house deal with partnerships both matrinimonial and professional, trade, journey, death.
This house deals with sudden events, longevity, in-laws, occult.
This house deals with father, higher education, wives brother, religion, fortune.
This house deals with profession,
This house deals with income
This house deals with expenses.
1 5 9
1 4 7 10
6 8 12