I'm not an real expert, but here's some info from my informal exploration of meditation with wikipedia links to get you started:

Tibetan Buddhist mindfulness ("Vipassana"): Vipassan

Zen Buddhist practice ("Zazen"): Zazen - Wikipedia, the free encyclopedia

Tibetan Buddhist concentration ("Samatha"): Samatha - Wikipedia, the free encyclopedia

Tibetan Buddhist compassion ("Tonglen"): Tonglen - Wikipedia, the free encyclopedia

"Focusing": Focusing - Wikipedia, the free encyclopedia . This is actually a technique of Western psychotherapy, but it's quite similar to meditation.