Systema Sephirotica

Tree of Life

Each of the following are emanations of God, Ein Sof is what god really is, but this will never be known by man. The ten Sephira form the Tree of Life and present different aspects of what God is in this world.
The Tree has three pillars, which represent the three basic principles of Consciousness, Form and Force.
The sephirotic Correspondences are certain associations and qualities unique to each Sephira, they provide a grip (pointer) on the elusive concept behind the Sephira.
The obvious correspondence in the Tree of Life on the right is the briatic colour. The briatic correspondence is an abstract quality that describes the way the Sephira expresses itself (i.e. how we would recognize it).
Virtue and Vice are the two sides of the coin, the positve and negative influence of this special Sephira. Then there is the illusion, that is the way that the energy of a Sephira distracts ones view and clouds ones judgement.
Qlippah is the shell. Each Sephira was seen to add a new shell around the true self of God, disguising the divine energy further.
Obligation is a quality a person dedicated to a certain Sephira has to have.
There are more correspondences, such as the name of God (which is used to invoke the Sephira's power in the world of emanation), the assigned Archangel or the angel-order itself.
I strongly recommend to have a look at Colin Low's Notes on Qaballah, on which this rather short summary is based.