One of the causes of the problems in Russia’s sad history in the 20th century was the use of imported words which people didn’t fully understand. “Revolution” (or the Russian word “revolyutsia”) was one of these.

"My heart burnt within me with indignation and grief; we could think of nothing else ... Every one is feeling the same. I never knew so universal a feeling." (Elizabeth Gaskell 1865)

Slavery is the idea that a human is someones property, that he/she can be bought, sold and owned; and forced to work without being paid. This concept has been around for thousands of years and all major civilizations used slaves at some point.