There are so many different types of Magnesium, yet they are so needed for our body's flow
This is from an article I just read..."this nutrient is responsible for 300-600 different biochemical reactions in the body (including metabolism)… when your levels are low, you struggle with sleep, energy, metabolism, pain and more."
Magnesium Chelate is especially important for muscle building, recovery, and health. 
Magnesium Citrate helps with the effects of obesity.
Magnesium Bisglycinate is most often used to treat symptoms of too much stomach acid such as stomach upset, heartburn, and acid indigestion. 
Magnesium Malate is thought to be the most bioavailable form (found naturally in fruits, giving them "tart taste.")  It can help with migraines, chronic pain, and depression.
Magnesium L-Threonate (MgT), is important for the brain because it improves learning abilities, working memory, and short- and long-term memory. 
Magnesium Taurate is best for your heart.
Magnesium Orotate helps your heart, too, and is believed to be the best form for metabolic improvements. It enhances recovery, energy, and performance.