The key is to understand the basics and determine what it means to your day-to-day consumption. Cannabinoids are an incredibly important part of this as they are the chemical compounds secreted by the flower that provides different effects (both mental and physical). The two most common types, and the ones we will focus on, are THC and CBD. 

THC (aka Delta-9-tetrahydrocannabinol) is the psychoactive compound found in the cannabis
Plant. THC strongly binds to receptors in the brain, which is why those who consume it are more likely to report feeling "euphoria" after consuming it, often described as feeling “high”.

CBD (aka cannabidiol) is the non-psychoactive compound found in the cannabis plant that is not typically associated with euphoric or “high” feelings.

Strains have varying levels of both of these, plus some other cannabinoids - so it's best to find which one(s) you prefer and be familiar with their effects.