In business, handling products in different units of measure is very important and it's very essential to sell and buy products in different quantities that are convenient for consumers.
Units of measures are an indication citing the unit used to handle a particular product. Thus the concept- Unit of measure arises from purchasing a product either in bulk or in fewer quantities.
One can easily configure the unit of measure in Odoo for a particular product.
For this go to Sales - Configuration - Settings - Enable Unit of Measure
After enabling Unit of measure go to configuration - Units of measure
Under the Unit of Measure, you can see a menu: Unit of Measure Categories