Today's word is the verb DO (dare, dedi, datus). You can get a sense of how common, and archaic, this verb is, since it has the reduplicated form: dedi. There are some other common Latin verbs that you know with this type of perfect, such as memini, cecidi, tetigi, momordi, etc. In archaic Latin there were even more reduplicated perfects that what you see in classical Latin; in Plautus, for example, you can still see the perfect for tetuli, which was supplanted by tuli in classical Latin.
The perfect form dedi gives you a clue about the etymology of the verb credo, which is actually a compound of cre (cor) and do, as you can see from the perfect form credidi. To believe something in Latin is to give your heart (mind) to it. You can also see the perfect form in other compounds of do, such as trado (tradidi), reddo (reddidi), and perdo (perdidi), etc.
In English, we actually use the Latin word data, which is the neuter plural of the participle; datum is the singular. Of course, it causes all kinds of confusion that data is a plural in English; there is an increasingly common tendency to treat data as a mass noun (singular) in English, in addition to the traditional use of data in the plural.
Here are some examples of today's word in Latin sayings and proverbs; for more information, see the page at the Scala Sapientiae, which also contains notes on some of the proverbs cited below, as well as additional proverbs:Deus omnia non dat omnibus.
Do ut des.
Qui non habet, ille non dat.
Cui des videto.
Deus dat cui vult.
Nihil dat qui non habet.
Cui multum datum est, multum quaeretur ab eo.
Da, si vis accipere.
Dare Deo accipere est.
Quod datur, accipe.
Qui petit a te, da ei.
Accipe quod tuum alterique da suum.
Frater est amicus quem nobis dedit Natura.
Nox dabit consilium.
Date, et dabitur vobis.
Petite, et dabitur vobis.
Non cunctis dat cuncta deus.
Gratis accepistis; gratis date.
Quae gratis accepimus, gratis demus.