You also have to realize that the Hebrew language is quite small. One individual can memorize every word in the language so attempts at producing new translations from the same available manuscripts can produce slightly different translations in terms of OT material. Not all linguists agree on how words translate. Often times the differences are very slight, but occassionally they're significant.
For example, the word "yom" in Hebrew means day, but "yom" can be translated according to 5 or 6 correct definitions. In terms of the Genesis creation account some textual critics say "yom" means a literal 24-hour day and other textual critics say that same "yom" means an age or expanse of time. In this case the context is needed to help define, but (in this case) the context still has support for both young and old earth creationist perspectives.
Now the Greek language is more robust so the available NT manuscripts typically provide more consistent translation since there's an easier "1 for 1" link between english and greek terms.
It's tough to say which is the best translation, but again modern scholarship heavily replies upon the NASB, NIV, ESV and NLT. Some still ONLY utilize the KJV, but that translation contains antiquated english....hence the modern translations we have now.
If there is a passage of verses you really want to dig in on there are plenty of great online tools that will take each verse and compare it across every available translation.
