Misdemeanor and felony were terms that both existed, but didn't have the same technical existence as they do today. Misdemeanor should be taken literally: mis-demeanor, basically a form of bad behavior, which may or may not be illegal. "High crimes and misdemeanors" then means crimes and sufficiently bad behavior in office, not literally the commission of a crime classified as a misdemeanor. Felony was closer to the current technical, in that it was any crime bad enough that you would have to forfeit goods or land. But they might have had in mind that committing a felony, while bad, was not necessary relevant to whether you should hold office. A "high crime" would be a crime of corruption, moral turpitude, etc (felony or not) and a misdemeanor would then be a blanket term of "any behavior bad enough that congress thinks it warrants removal". So it's both more precise and broader than either "high crimes and felonies" and "felonies and misdemeanors" would have been. Note that felonies are specifically mentioned in regards to interstate extradition in the Constitution. More on reddit.com

I've never been more terrified than when traveling into Johannesburg, South Africa. Our business partner drove us into town and she started removing her earrings, wedding band, etc. I asked her why and she said that the bandits would cut jewelry off of you if they stopped your car, so it's better to put it in the glove box. Our client was a major bank; to enter, you had to stand in a tiny plexiglass airlock where the guards (with machine guns) could inspect you before letting you inside. Once in, it was just like any other business anywhere - cubicle farms and conference rooms. More on reddit.com