* les deux: This is the most common and literal translation for "both." It means "the two."
* tous les deux: This is used when referring to two specific people or things. It means "both of them."
* l'un et l'autre: This is used when referring to two general things or concepts. It means "one and the other."
Here are some examples:
* J'aime les deux couleurs. (I like both colors.)
* Ils sont tous les deux venus. (They both came.)
* L'un et l'autre sont importants. (Both are important.)