Ribose, primarily seen as D-ribose, is a monosaccharide.

As a component of the RNA that is used for genetic transcription, ribose is critical to living creatures. It is related to deoxyribose, which is a component of DNA.

Ribose is also a component of ATP, NADH, and several other chemicals that are critical to metabolism.

References

Merck Index, 11th Edition, 8205.