A chorus pedal is a modulation effect. The original signal is split and run through a short delay and then combined with the original signal. The delayed part of the signal can then be modulated to create movement to create a thicker tone. A classic effect used on elctric, acoustic and bass guitars.
Reverb pedals modify the signal in such a way that you can replicate playing in different sonic spaces. Delay pedals allow you to repeat your sound at pre-determined intervals after you've played it. Both effects whether used independently or together can add warmth and depth to your tone. Reverb and delay pedals are collectively known as time-based effects and are typically positioned at the end of your signal chain.
