Organ donation is simple in words. But absolutely difficult (yet very simple for determined individuals)

Bone Marrow donation

Eye

Kidney

Liver

Lungs

Tissue donation

Body donation

We dont have separate pages for following donations
Hands & face
Worldover they are hardly done.
These are difficult surgeries. They call them vascularized composite allograft (VCA) organ transplants.

Stem cells
Bone marrow : Soft tissue is inside your bones. It produces many blood cells. Doctors remove it to get stem cells.
Cord blood stem cells (The blood in the cord that connects a newborn to the mother during pregnancy has high levels of blood stem cells. Doctors can collect and store these in freezers for a long time)
Peripheral blood stem cells: You can get daily injections of a drug called filgrastim. The drug increases the number of stem cells in the blood. It helps push out the same types of stem cells found in marrow. Doctors can collect this in the same way as when you donate blood.