“Non-finite Verb: also nonfinite verb. A form of the verb that does not display a distinction in tense, in contrast with finite verb (where there is a distinction between present tense and past tense: hopes, hoped). A non-finite verb is either an infinitive or a participle. There are two infinitives: the to-infinitive (‘Estelle wants to dance with Matthew’); the bare infinitive (‘Philip will come with Matthew’). There are two participles: the -ing participle or the present participle (‘James is playing cards’) and the -ed participle or (according to its function) the past participle or passive participle (‘James has visited me recently’; Jane was helped by Jeremy).”
Excerpted from: McArthur, Tom. The Oxford Concise Companion to the English Language. New York: Oxford University Press, 2005.