I see you are using simplified Chinese. If you use traditional Chinese, you wouldn’t get confused, because they are two different characters: 幹 (bad word) and 乾 (dry).
Anyway, “gan” is a swear word in Taiwanese, so people who use “gan” will always be using traditional Chinese characters.
Anyway, “gan” is a swear word in Taiwanese, so people who use “gan” will always be using traditional Chinese characters. Interestingly enough, I believe the real character for “gan” should be 姦, but we use 幹 as a substitute word. In Taiwanese, “gan” basically means “to fuck” (both in meaning and also the taboo behind cursing it).
You may have heard of the infamous swearing in Chinese, 操你媽 (fuck your mom). Well, we don’t say that in Taiwan; instead, we say 幹你娘, which is so offensive that Taiwanese people consider it as our “national curse” (國罵), meaning that nothing you say can be more offensive than that.
You can also use “gan” by itself, which is still very offensive, but if you are cursing at a situation and are around your friends, it might be considered acceptable. When Taiwanese people want to swear, usually we say either “gan” or “kao beh”. My personal swearing habit is to curse “gan” when something bad happens, and if something bad happens again within a few seconds, I would follow up with a “chao gan” (超幹)
There is also something known as “gan hua” (幹話), which basically means “bullshit that you say that sounds like you answered a question, but in reality, it’s just bullshit”. And if you are really good at bullshitting, people might even crown you as the “King of Bullshitting” (幹話王). Although you can use that against anyone you dislike, I think most Taiwanese netizens use it to describe a certain Taipei city councilor who looks like a Chucky doll and screams at people every day.
Finally, because “gan” is considered so offensive, TV stations will not air this word. If you ever watch Taiwanese TV, and you see an “X” being suddenly placed in the middle of a sentence, you can bet it’s supposed to be “gan” (X話 = 幹話, etc)