1) Blessings for Enjoyment:

A person is required to recite a blessing before receiving any sort of benefit or pleasure from this world. We recognize that everything in this world was created by, and is the property of G-d. Therefore we must "ask for permission" before indulging. Perhaps more importantly, constantly acknowledging this idea also reinforces in our own minds the conception of G-d's authority over everything.

Therefore, one is obligated to recite a blessing before eating or drinking, and before enjoying a pleasant fragrance.

2) Blessings for Mitzvahs:

We are required to recite a blessing before performing any Mitzvah. The blessing is "Blessed are You, Lord our G-d, King of the universe, who has sanctified us with His commandments, and commanded us to..."

By reciting these blessings we acknowledge that we are honored to have the opportunity to fulfill G-d's command. There is no greater privilege than to connect to the infinite G-d through observing His Mitzvahs.

3) Blessings of Thanksgiving:

We recite a blessing whenever we are the beneficiary of a divine kindness. Examples include: one who survived a major trauma, recovered from a serious illness, chanced upon a fortune, or had a baby.

Also included in this category is the blessing we recite upon receiving painful tidings. We recognize that ultimately everything which G-d does is for our best. We acknowledge this by saying "Blessed are You, Lord our G-d, King of the universe, the true Judge."