Gaius Valerius Catullus was born in the city of Verona some time around 84 BCE. We think that he died about 55 BCE. We don't know much about him beyond what we find in his poems, even though he himself warns us not to put too much trust in what is said there.
Catullus went to Rome early in life and spent most of his time there, with the exception of his service on the staff of C. Memmius, governor of Bithynia in 57/6 BCE. He does not seem to have liked his commander or army life. His political sentiments appear to have been Republican; at least he did not like Julius Caesar or the people around him much. He was part of a group of poets who are called "new poets" because they drew their poetry from Greek Hellenistic literature. Many of Catullus' poems seem to have been addressed to a lover whom he calls Lesbia. It is likely that this was a pseudonym for Clodia, sister of P. Clodius Pulcher and wife of Q. Caecilius Metellus Celer.
The poems of Catullus included here are written in two lyric meters: Hendecasyllabic (poems 7 and 10) and Sapphic (poem 11).
For an excellent introduction to Catullus' work, life, and socio-political context, as well as a spirited translation of his poetry, see The Complete Poetry of Catullus, translated and with commentary by David Mulroy (Madison: University of Wisconsin Press, 2002).
Alison Barker's Links for the Study of Catullus will take you to many interesting sites on Catullus and his poetry; see also Henry Walker's web edition of the Poems of Catullus, with Latin text and facing English translation.