In natal astrology, astrology applied to individuals, the Sun, Moon and planets symbolize basic human needs, desires or urges which we all possess. The birth chart is a symbolic map of the solar system as seen from the earth at the time and place of birth. The planets of the chart are described in three basic ways.

Aspects (angles) formed between the Sun, Moon and planets, as seen from the earth indicate the relationship between the planets. Each planet is located in a particular sign of the zodiac. Each planet is also located in a particular house, these are the twelve divisions of the chart. The first house is the ascendant.

It will be seen that although many people may have Mars in Scorpio, or Venus in Capricorn, and hence have certain traits in common, the number of ways in which the three factors of planets, signs and houses can be combined is infinite. Your birth chart is therefore a unique blueprint of your personality, everyone is different. At birth, the chart represents a set of potentials, it describes the "form" of your personality, the contents must be added through the experiences of life. Indication of these experiences are sometimes seen through the transits or cyclic movement of
the planets.

The Planets

The Sun, Moon and the inner or personal planets; Mercury, Venus, Mars, Jupiter and Saturn represent various drives, or urges within the total personality. Just as in the body the various organs; heart, kidneys, liver etc. perform their own specific functions yet operate as part of a total system; so the planets can be regarded as symbolizing the "organs" of your total personality. The aspects (angles) between the planets show how these functions interact with each other.

Outer Planets

Uranus, Neptune and Pluto, move through the signs so slowly that the sign positions of these planets refer more to the generation of which we are a part, rather than individual characteristics. It is the house position that shows where we will meet with the principles expressed by these planets in our lives. The aspects between the outer planets and the personal planets indicate a level of understanding of the principles which the outer planets
represent.  These planets can't be seen without a telescope. Therefore they represent forces and levels of reality beyond our experience. They do this by breaking down the boundaries of the ego (symbolized by Saturn), to allow the inflow of higher ideals and goals into our ego-centered minds. This can often mean the total disruption or destruction of our existing lives, goals, or outer and inner structures in order to make this possible. 

Aspects 

Conjunctions are two planets at the same place where their energies merge together.

Trines (120 degrees), and sextiles (60 degrees), between two planets
represent inherent abilities or talents.

Squares(90 degrees) and oppositions (180 degrees), show that there is some stress or tension between the planets which indicate inner conflicts and tensions (conscious or unconscious) that you will be forced to recognize and express in a positive way. If you are not conscious of these inner conflicts, they will be met through seemingly "fated" external events or in relation- ships with others.

The above does not necessarily mean that trines and sextiles are "good" and squares and oppositions are "bad". A chart dominated by flowing aspects may indicate someone for whom everything comes too easily, they will therefore lack any real motivation and may not achieve much during their life. A chart with hard aspects, on the other hand, may indicate someone who driven by his or her own inner conflicts, can achieve something of real worth in their lives. The stressful aspects are as necessary to us as the flowing aspects, and most of us are a fairly even balance of both. 
 

The activity of each planet is further modified by the sign in which it is
placed, the effects of these modifications case will be described in the interpretation.

Houses

The birth chart is divided into twelve sections. These represent the
division of space surrounding you at birth. The sign on the first house " cusp" (the point that marks the beginning of the house) is the sign that was rising over the horizon at the time and place of your birth, this is your rising sign or ascendant.

The sign on the seventh house cusp is the sign that was setting at the time of your birth and is called the descendant.

Each house represents an area of life experience. The positions of the planets in these houses therefore show in what areas of experience the effects of these planets will be most noticeable. The Ascendant is an important point and has its own particular meaning.

Ascendant

The ascendant is the sign that was rising over the horizon at birth and it's position is dependent on both time (it changes by 10 degrees every hour) and place of birth (someone born at the same time on the opposite side of the world will have the opposite sign rising). The planet that rules the sign is said to be the ruler of the chart. Hence the sign and house position of the ascendant's ruler are of particular importance.

The ascending sign shows the way we approach life and the world in general. It can be related to what some psychologists call the persona, the mask we place between our inner selves and the world. As such it shows the way in which we are perceived by others, at least their first impressions of us. 
The ascendant represents the kind of energy and types of activities that we need to enliven us physically.

Transits

The positions of the planets in your chart are fixed, but the planets still continue to move around the zodiac after birth. Each planet has its own characteristic cycle. For example, Mars takes two years to complete one full cycle, Saturn takes 28 to 30 years. In doing so they pass through the houses of your chart, and make aspects to your natal planets, bringing about experiences that are related to the nature of the transiting planet, the house it is passing through and the planet being aspected.

By following the transits you can see the timing of experiences, from times of opportunity to major life crises. This brings an understanding of how and why you have experienced certain things in the past, also your present experiences, and what you may experience in the future.

Transits cannot predict events but only the type of experience you will have at a certain time. At all times you have free will as to how you react to these experiences, and whether the planetary energies involved are used positively or not.