Have you ever wondered how these words ended up with a letter "c" in some of the forms? That "c" is a remnant of an emphatic particle "ce" that was added to the root form of the pronouns. So, in archaic Latin, instead of hic-haec-hoc, you had hice-haece-hoce. You could even see the "c" in some forms of the pronoun that don't have a "c" anymore, such as the genitive plurals - you know the forms horum and harum, but in archaic Latin you can find the forms horunc and harunc. Likewise for the genitive: you are used to the form huius, but in older Latin you can also find huiusce. You might also have seen this form in the expression huiuscemodi (for huiusmodi - huius modi).
You can also see a remnant of this emphatic "ce" in other Latin words, such as nunc and sic. Another place you can see the "ce" particle is when "ne" is added, which causes the "ce" to change to "ci" - as in the expressions hicine and sicine.
In order to understand the meaning of the hic-haec-hoc pronoun in Latin, it helps to see it as part of a series: hic-haec-hoc refers to something closest to me, the speaker - you can think of it as a kind of first-person demonstrative pronoun. The pronoun ille-illa-illud refers to something over by someone else, not something near me - you can think of it as a kind of third-person demonstrative pronoun. Finally, there is the pronoun iste-ista-istud, which refers to something with a special relationship to you (often with a pejorative sense) - "that thing of yours, not mine," something like a second person pronoun.
Adverbs. It's important to remember that hīc can be used as an adverb meaning "here, in this place." Likewise, remember hinc, "from here, from this place, hence" and huc, "to here, to this place, hither."
Here are some examples of today's word in Latin sayings and proverbs; for more information, see the page at the Scala Sapientiae, which contains notes on some of the proverbs cited below, as well as additional proverbs:
Quod sumus, hoc eritis.
Hoc unum scio: me nihil scire.
Quod tibi vis fieri, hoc fac alteri.
Quod tibi, hoc alteri.
Hoc unum certum est: nihil esse certi.
Post hoc, ergo propter hoc.
Patria mea totus hic mundus est.
Quod in corde, hoc in ore.
Hic perierat et inventus est.
Nobiliter vivens et agens, haec nobilis est gens.
Hoc sustinete, maius ne veniat malum.
Cui deest pecunia, huic desunt omnia.
Hoc retine verbum: frangit Deus omne superbum!.
Hoc portat leviter, quod portat quisque libenter.
Haec olim meminisse iuvabit.
Nunc hunc, nunc illum consumit gladius.
Quae fieri fas est, tempore haec fiunt suo.
Cui deus auxilio est, huic onus omne leve est.
Hunc fidum dico, bene qui succurrit amico.
Multa rogare, rogata tenere, retenta docere: haec tria discipulum faciunt superare magistrum.