Explain stem cells to me
Stem cells are specialized cells that have the ability to divide and generate other types of cells. They can be found in various tissues throughout the body, including blood, brain, skin, and bone.

There are two main types of stem cells: embryonic stem cells and adult stem cells. Embryonic stem cells are derived from the blastocyst stage of an embryo and have the capacity to become any type of cell in the body, while adult stem cells are located within the body and can only differentiate into specific types of cells, such as neurons or muscle cells.

In theory, stem cells could potentially replace damaged or diseased cells in the human body and help repair and regenerate injured tissues. This has led to considerable interest in using stem cells for therapeutic purposes, particularly in the field of regenerative medicine.

For example, researchers are exploring the potential of stem cells to treat diseases like Alzheimer's disease, multiple sclerosis, and Parkinson's disease by replacing damaged cells in the brain. Additionally, they are exploring the use of stem cells to promote healing after surgeries and injuries, as well as to aid in the development of new organs.

While there is still much research needed to fully understand the potential benefits and risks of using stem cells, their widespread availability and promising results in animal studies suggest that further study may lead to many valuable clinical applications in the future.