As verbs the difference between praise and appraise is that praise is to give praise to while appraise is to set a value; to estimate the worth of, particularly by persons appointed for the purpose; as, to appraise goods and chattels or appraise can be (proscribed) to apprise, inform.

As a noun praise is commendation; favourable representation in words.

Example:
1. He is worthy of our praise.
2. Do not praise a day before sunset.
3. An employer should appraise the ability of his employees.
4. Managers must appraise all staff.