Transcendental Meditation

Sometimes called Zazen, it involves specific steps and postures and is studied with a teacher. 

The goal is to find a comfortable position, focus on breathing and mindfully observing one's thoughts without judgement.

Also known as Metta meditation; the goal is to cultivate an attitude of love and kindness toward everything.
During meditation, practitioners send and repeat messages of loving-kindness, until they feel an attitude of loving kindness. 

Practitioners usually learn from a teacher or do a class. 

Kundalini yoga blends movements with deep breathing and mantras.

The goal is to notice tension and to allow it to be released.
Practitioners start at one end of their body, usually their feet, and work through the whole. They might tense and then relax muscles or they might visualize a wave moving over their body to release tension.

It encourages practitioners to notice their surroundings without judgement, instead of dwelling on the past or future.

Mindfulness can be done almost anywhere, even in a grocery store, for example.

It encourages mindful breathing.

Practitioners breathe slowly and deeply, counting or focusing on their breaths and ignoring all the other thoughts.