The three main components of a natal birth chart are the signs, the planets, and the houses. The signs is the 12-fold cycle of the zodiac and describe a circular rhythm and is one of the more popular aspects of astrology. The planets refer to the sun and the moon and the other planetary bodies in the solar system. And the houses will show where an energy could be expressing itself or where a certain tone is received in the field of human experience. As stated by mountainastrologer.com, "The planets show what is happening, the signs show how it's happening, and the houses show where it's happening."
The Signs
We are all familiar with the 12 zodiac signs: Aries, Leo, Sagittarius, Taurus, Virgo, Capricorn, Gemini, Libra, Aquarius, Cancer, Scorpio, and Pisces. These signs are basically areas in the constellation where the planets pass through in a course of time. Where the planets are tell a lot about a person's character. When a chart says that "Venus is in Leo," it means that Venus was on that sign on the time of birth, and when it says "at 15 degrees of Leo," Venus passed about halfway through that part of the sky associated with that particular zodiac sign. All planets will pass through all the signs.
The 12 signs have an influence on a person all the time, and the energies of the 12 signs are present at the time of birth in various ways.
The Planets
Each planet in the birth natal chart represents a function in a person's personality. They are grouped into two categories: personal planets (Sun, Moon, Mercury, Venus, and Mars) and outer planets (Jupiter, Neptune, Saturn, Uranus, and Pluto).
To get an idea of what each planet represents, here's a general description. In the personal planets, the Sun represents a person's basic identity, their purpose and will to exist. The moon, reflecting the light of the Sun, is the container of life experiences. It is a person's way of being or a way of relating to life that would feel natural comfortable. The moon does not represent emotions but is connected to it and the memories attached to these emotions.
Mercury relates to a person's ability to perceive to and relate with individuals and objects other than themselves, which makes connected with communication, symbols, and language. Venus is the part that gives feedback about what is comfortable or not, what that person enjoys; it is an indicator of what a person values and appreciates. Mars functions to as upon the desires and needs as described by Venus; it represents action and the use of will.
In the outer planets, Jupiter represents growth and the ability of a person to integrate into society; it represents the person's life path. Saturn represents responsibilities, the rules a person establishes, the necessary restrictions imposed for the growth of one's consciousness. Uranus represents the ability of one to break through new levels of understanding or consciousness, gaining insights from life's difficulties and problems. Neptune represents a person's ideals and imagination, the breaking of psychic boundaries and bringing about a sense of harmony with the universe. And Pluto represents change and inner growth, the kind of change that starts deep in a person, touching upon sensitive psychological areas.
The Houses
Mountainastrologer.com states that the houses are the frame of reference through which a person can identify the planet's positions against the background of the zodiacs. The 12 houses similar with the 12 signs of the zodiac. Elbertwade.com provides a very concise description for each house. The first house refers to the outer self, the second house refers to wealth, the third house refers to the worldly mind or to explorations and research of all kind, and the fourth house refers to family and security.
The fifth house refers to the expressions of the mind or creativity, the sixth house refers to responsibility, the seventh house refers to relationships with other people, and the eighth house refers to desire motivations and their intensity.
The ninth house refers to the higher mind or religious and philosophical ideas, the tenth house refers to career choices and a person's potentials, the eleventh house refers to social life or community, and the twelfth house refers to hidden limitations or all those we go through to make our dreams a reality.
And those were the basic components of a natal birth chart and overview on each component to understand how it all works. Individually, it doesn't seem to make much sense, but once all these three components are analyzed together, it will give a person a very revealing glimpse into their character.