The Difference Between Praise & Worship:
Praise is giving God accoldes for the mighty acts He has done, His powerful acts, How He moved on our behalf, praise talks about what our God has done and will do.
Worship is different, It is appreciation, adoration for Who God is!.
When we worship we begin to describe WHO He is - you talk about His character, His person. we tell Him how Loving and Kind He is, How Great He is, How He is a wonderful Father, provider, protector (if you notice these are not "acts" but His character, who He is_
Sometimes it causes you to bow down in His presence because He is so sweet, so overwhelming with His love and mercy - there will be times you cannot physically stand, but only bow in His presence, after all - He is the King of Glory.
TIP: ANYBODY can praise God for what He has done, but it takes someone who has experience in knowing Him, they have developed an intimate relationship with the Lord by spending time with Him, like David. Their relationship with the Lord has been birthed through the trials of life, suffering, fasting, prayer, reading His Word, obeying and dying to self, that worship is born out of getting to know God personally.
I saw this quote: "Praise is the fruit of the lips; Worship is the fruit of the heart"