In general terms, praise may be defined as approval or admiration toward someone.  Praise to God is the acknowledgement of who He is.  It is exalting Him and thanking Him for His attributes and His ways.  It is expressing to Him and to the world how great He is.

I think this is a good definition of praise.  But there is so much more we can say about it.  There are three different Hebrew words in the Bible, yadah, halal, and barak, which help us to see what praise is.  Let’s take a look at each of these, one at a time. 

Praise as thanksgiving (from yadah).  Thanksgiving by itself or thanksgiving without praise is the mere acknowledgement of God’s past mercies; it is gratitude only for God’s goodness toward us.  But thanksgiving as praise (from yadah) is not only giving thanks for past mercies, but for all His works—past, present, and future—and for all his attributes.  It is also showing gratitude to God not only for His goodness to us, but for His goodness to all people.  

This Hebrew word yadah, found 120 times in the Old Testament, including some 70 times in the Psalms, is translated as praise but it gives us the idea of giving thanks to God.  It not only gives the idea of giving thanks for His works, but also of giving thanks to Him who performed the works. 

For an example, we see in Psalms 42:5, that David, while being in great despair, remembered how God helped him in the past.  And so, he said to himself, “Hope in God, for I shall again praise Him [yadah] for the help of His presence.”  So we see that David thanked God not only for His help, but also for His presence, or for His person, who is the source of help.

Again, we see this word yadah in Psalms 67.  The Psalmist writes in verses 5 & 6, “Let the peoples praise Thee, O God; Let all the peoples praise Thee.  The earth has yielded its produce.”