be aware that port 80 is http traffic i.e web traffic
Nope, thats only if he's hosting a server. Whenever he accesses a website a request goes out from a random port over 10xx, into the web server on port 80.I was gonna mention that.
Doesn't that mean if he closes it then he won't be able to access the web?
If he has no need for it why keep it open for possible attacks?i think you should keep it open, I dont think any super hacker would hack you