Praise is the making of positive, encouraging statements about a person, object or idea. Referring to people and their actions, it is the opposite of reproof. Praise is meant to encourage the continuation of good behavior. Most people are responsive to praise and will increase in self-esteem or confidence when praised.
Praise, like reward, is often given by someone in higher status, because they are in a position to judge other people's doings and give praise as well as reproof, as the case may be. For example, parents may praise their children and teachers may praise their students when they do well.
However praise can also be given from a low to a high status role, typically taking on a form of compliment, admiration or reverence. For example, a fan may praise an actor, film, artist, artwork, writer, story, etc.
In religion, a deity may be praised by their believers. Here too, praise is given from the low to the high status.