Schools

It isn't practical to give a full overview of all ancient Greek philosophical schools in this space, but here's a quick run down of a few to get you started:

Pre-Socratic philosophers: were interested in understanding the natural world 

Sophists: emphasised practical skills and rhetorical techniques. 

Platonists: believed in the existence of a transcendent realm of eternal truths. One of the most theologically focussed ancient schools. 

Peripatetics: the school of Aristotle emphasised empirical observation and logic. 

Cynics: rejected conventional social norms and values. 

Stoics: emphasised self-control and living in accordance with nature.

Epicureans: believed that pleasure was the highest good, but that true pleasure could only be attained through modest and simple pleasures.

The Pythagoreans: were focused on the study of mathematics, music, and the underlying order and harmony of the universe, which they believed reflected the divine nature of reality.