The better concordances are comprehensive and list all usages of almost every word, and from which Geek, Aramaic, or Latin word they were translated.

Young’s Analytical Concordance uses the alphabetic according-to-English filing method, keyed to KJV, with lexicons of Greek and Hebrew (Aramaic) toward the back. This allows a reader to find out what Greek or Hebrew word an English verse represents, and then refer from the English concordance to the lexicons and back again to follow every use of a word to develop a full sense of meaning.

Young’s is easy to use. But it has frequent and annoying glitches wherein the Greek or Hebrew listed as being the original word is not actually the one used in the text.

Strong’s Concordance, a popular concordance thought to be among the best, uses a numerical cross-reference system. It is a bit more complicated, but the numerical system is keyed into many important reference materials, such as Bullinger’s Companion Bible.

Concordances may be found to versions other than KJV.