Modern English did not happen over night. It evolved over time, taking in words from other languages around the globe. "Etymologies are not definitions; they're explanations of what our words meant and how they sounded 600 or 2,000 years ago," states the Etymology On-Line Dictionary.
Generally, the dates beside a word indicate the earliest year for which there is a surviving written record of that word. Know that over 50% of the English language has Latin roots; however, no one really speaks Latin.
So where do all these words come from? You are going to find out!