There are so many things to do during the summer. You can work, travel, or even just hang out with your friends. Basically, there's a lot of ways to keep busy.
But there's also the nights when nothing is planned, and you're perfectly content not leaving your house. This doesn't even apply to just summer. It could happen any time of the year.
One of my roommates and I have gotten into a weird routine where if we're both home and doing nothing we'll sit and watch stand-up specials on Netflix. We get to relax while listening to funny people; what more could we ask for on a night off?
Of course, there's much more to watch then stand-up shows but these nights have proven to me that sometimes I don't need plans to have a fun night. Sometimes I just need some friends and a TV. Or I could take a different route and just stay in and play some games. No matter what I decide to do, I know that I can still spend time with the people I care about, and as an added bonus, I don't even need to spend anything.