Testimonies - those things to which God witnesses
Law - that which points the way
Precepts - mandates handed down to be observed
Statutes - something that is engraved, cut; it is a definitive standard, set forth in a manner that is intended to last
Commandments - those thing God requires, enjoins with authority
Judgements - a legal term meaning, "decisions handed down"; court verdicts (case law) divinely given
An excellent example can be found in Psalm 19:7-11
The law of the LORD is perfect,
converting the soul;
The testimony of the LORD is sure,
making wise the simple;
The statutes of the LORD are right,
rejoicing the heart;
The commandment of the LORD is pure,
enlightening the eyes;
The fear of the LORD is clean,
The judgments of the LORD are true
and righteous altogether.
More to be desired are they than gold,
Yea, than much fine gold;
Sweeter also than honey and the honeycomb.
Moreover by them Your servant is warned,
And in keeping them there is great reward.
The word of God is an amazing thing. Something that I hope I will never cease to be amazed with.
Open my eyes that I may behold
Wonderful things out of Your Law.
Psalm 119:18 (Translation by Jay E. Adams)
*(All definitions from Jay E. Adams book, Counsel from Psalm 119)