Tree rings, also known as growth rings or annual rings, are concentric circles that can be seen in the cross-section of a tree trunk. Each ring represents a year of growth, with the width of the ring indicating the rate of growth during that year. Tree rings can provide valuable information about a tree's age, growth patterns, environmental conditions, and climate history. Dendrochronology is the scientific study of tree rings, and it is used to date archaeological and historical artifacts, study past climates, and understand forest ecology. By analyzing tree rings, researchers can reconstruct past climate patterns, identify periods of drought or disease, and track environmental changes over time.