Answer:
An art-form and a web-browser.
What can travel around the world while staying in a corner?
It is the time in your life when you simultaneously know everything and nothing at an instance.
I have many letters, And though it's strange to say, I stay the same no matter how many I give away.
I give milk and have a horn but I'm not a cow. Who am I?
A caribbean shape that makes ships disappear.