Lard is a semi-solid white fat product obtained by rendering the fatty tissue of a pig. It is distinguished from tallow, a similar product derived from fat of cattle or sheep. Lard can be rendered by steaming, boiling, or dry heat. The culinary qualities of lard vary somewhat depending on the origin and processing method; if properly rendered, it may be nearly odorless and tasteless. It has a high saturated fatty acid content and no trans fat. At retail, refined lard is usually sold as paper-wrapped blocks.

Source: Wikipedia