A Lien is an encumbrance against the property, which may be voluntary or involuntary. There are many different kinds of liens, including a tax lien (for unpaid federal, state, or real estate taxes), a judgment lien (for monetary judgments by a court of law), a mortgage lien (when you take out a mortgage), and a mechanic’s lien (for work done by a contractor on the property that has not been paid for). For a lien to be attached to the property’s title, it must usually be filed or recorded with a local county government office.