What're embryonic stem cells?

Perhaps our future.: A human embryo consists of 50-150 embryonic stem cells 4–5 days after fertilization, and those few cells eventually differentiate into all of the different specialized cells that compose the entire human body. Since those stem cells can potentially be anything they want to be, the potential for curing multitudes of human disease, using them, is enormous.

Embryonic stem cells: All humans first start as a fertilized ovum, which is described as being totipotent ("potential to become every cell"). After several days, it grows into an embryo, comprised of embryonic stem cells. Embryonic stem cells are still very unspecialized and have the ability to divide endlessly and to develop into all of the 220 human cell types.