Kinases are a type of enzyme that play a crucial role in cellular processes by adding phosphate groups to other molecules, typically proteins. This process, known as phosphorylation, can activate or deactivate the target proteins, thereby influencing various cellular functions such as metabolism, cell division, and signal transduction. There are many different kinases, each with specific targets and functions. For example, protein kinases are the most common type, while lipid kinases target lipids. Dysregulation of kinase activity is often associated with diseases, including cancer, making them important targets for drug development.