When I earned my first money with the bounty, people around me (especially my family) asked me where did my money came from. When I told them that it came from bounty campaigns, I saw their puzzled face. So I explain it to them with this analogy: "When politicians are running for office, they always show their faces in public in order for them to remember. They give flyers with their name and platforms in it. ICOs are like politicians and their elections is called bounty campaign. We make the ICO popular by posting in forums, social media sites, and creating videos and article." And they quickly understood it so every time someone ask me about bounty campaign, I always used this analogy. How about you?
A bounty is a possibility to get tokens for free without an investment. You are being offered to perform some actions to promote the product and then you get a reward. For example: to join the TG channel, to repost something on Twitter.
Bounty hunters are people who are constantly searching for such campaigns. They have a hope to become millionaires in the next 3-4 years by doing this