Personal lubricants (colloquially termed lube) are specialized lubricants used during human sexual acts such as intercourse and masturbation, to reduce friction to or between the penis and vagina, anus, other body parts, or applied to sex toys to reduce friction or to ease penetration. Surgical or medical lubricants or gels, which are similar but not usually referred to or labelled as "personal" lubricants, may be used for medical purposes such as speculum insertion or introduction of a catheter.