The origins of masses of words in use today can be traced back several millennia, although things become fuzzier the further back you go. Sometimes the relationships are really surprising - in this first post I'll describe the first experience I had with etymology suddenly "clicking":
As Wikipedia will tell you, the word "robot" comes from a Slavic word meaning "forced labourer" or something of the sort. And when I was studying Russian I noticed the word работа (rabota) meaning "work" and I thought it was interesting that our English word went back to Slavic.
Then when I studied ancient Hebrew I noticed that the word for work was עבודה ('avoda, the first sound is a guttural which comes close to french or German R but not quite). Since B and V are closely related sounds (they are the same letter in Hebrew), and D and T differ only by voicing, the connection between Slavic rabota and ancient Semitic 'avoda, both meaning "work" was too close to be coincidence. Other sources confirmed my suspicions. Our modern word "robot" is thus related to - though not necessarily descended directly from - the ancient Semitic word for work.
Some other words it is related to are the Arabic عبد ('abd) meaning "servant" (you might know it from names like Abdul) and German Arbeit meaning "work".