An "alkyl" group is a type of hydrocarbon chain derived from alkanes, which are saturated hydrocarbons containing only single bonds. Alkyl groups are formed by removing one hydrogen atom from an alkane, resulting in a structure that can attach to other molecules. Common examples of alkyl groups include methyl, ethyl, and propyl. Alkyl groups are important in organic chemistry because they serve as building blocks for more complex molecules. They can influence the properties and reactivity of compounds, making them essential in the synthesis of pharmaceuticals, plastics, and other materials.