Just one thing, the one single thing you love about internet. Don't think just let your heart says quickly. Be honest and give your answer. For me its messenger who keeps me in touch with my beloved ones.
The multitudes of people who use it. It's the only place I have a halfway decent chance of meeting likeminded people, and the only place where I can talk with those people about some of my more unusual interests and opinions.
I probably like the internet a bit too much, but to semi-quote myself, 'the internet holds everything'! Seriously, you can learn almost anything and find anything so easily. I'm never not able to satisfy my curiosity.
1. Internet culture.
It's amazing how ideas circulate the web, jumping from one mind to the next. It shows us how culture evolves, and shapes the way we think, and can turn us from upstanding members of society into 14-year-old boys who think penis is the funniest word ever. It's fascinating.