Stoicism is enjoying a modern and a popular ( ordinary people, non-academics ) revival. This is likely due ancient Stoicism having the practical goal of leading a happier life and is also likely due to the success of cognitive behavioral therapy which has its roots in ancient Stoic philosophy.
Disclaimer: I know nothing of Stoicism and I am just starting to learn about it myself.
The goal of Stoicism is to learn to live in harmony with how things work ( your mind, life, other people, the laws of nature ).
The ancient Stoics believed that in order to live a eudaimonic ( worthy and happy ) life people need to understand 2 things:
The nature of the world
The nature of human reasoning
The ancient Stoics had 3 disciplines and 4 virtues they tried to cultivate for happy and worthy lives. They studied 3 main subjects to aide this pursuit.
The chart below shows the primary relationship between each Stoic discipline, virtue, and subject of study. Unfortunately, translators have picked English words for translations of key Stoic concepts that are the way contemporary English speakers understand those words. This is an impediment to understanding the ancient writings. The chart below includes a “modern translation” or an alternative choice of words for those key Stoic concepts. It is based on my personal understanding of chapter 2 of “How To Be A Stoic” by Dr. Massimo Pigliucci.