Carbides can be generally classified by the chemical bonds type as follows: 
# salt-like (ionic),
# covalent compounds,
# interstitial compounds, and
# "intermediate" transition metal carbides.
Examples include calcium carbide (CaC), silicon carbide (SiC), tungsten carbide (WC; often called, simply, carbide when referring to machine tooling), and cementite (FeC), each used in key industrial applications. The naming of ionic carbides is not systematic.