Ko te reo is the Maori Language.
There are basically three types of Reo.
Traditional or Classical Reo
This is the most beautiful form of our reo.
Many of the words and phrases of classical reo used are poetical references to events. They are also sometimes based on tikanga.
Classical reo has many subtleties. As our reo is an oral language and there is mana in the spoken word, by changing the tone of your voice you can change the meaning of a sentance.
The basics for tones is to ask a question you raise the tone of your voice at the end and to make a statement you drop the tone of your voice at the end.
The words used are pre-european and the sounds of the words themselves have mana.
This site and the tutorials use mainly the classical reo.
Modern reo is mainly transliterations of english words, for example mama for mother, kapu for cup.
Modern reo also has taken some of the more common words in english and uses them for all situations. While this may make it easier for the learner, the subtleties of the reo can come into play, and when speaking to a classical speaker, you can insult them without meaning to.
Poetical reo is the highest form of reo and based on tikanga and a knowledge of history. Many modern speakers of the reo use poetical phrases, but they use them because they sound good, not because they understand the underlying principles of the phrase.