A lot of people think that boxer briefs and trunks are the same, but actually, they are not. Boxer briefs are known to have longer legs, so those who would wear it can expect that it will also reach their thighs. When you say trunks, you can expect that the legs are going to be shorter, and they are also going to be squared off. Trunks may look like they are actual briefs that are very tight-fitting, while boxer briefs will look like tight-fitting shorts.
There was a time when men wore swimming trunks to the beach. Some men still do this right now, but there are more men who use swimming shorts now. They just use boxers or briefs when they are at home.