What does it mean if a website gives me this? Can I do anything?

What are those tabs you edited out OP?
Why was it so important that you edited them out before hand.

>>29527
They contain which university I go to. Just would rather not share it even though I realize there's no risk in 4chan knowing that some anonymous user goes to a university.

>>29525
It means that it's not sending the correct MIME type in the http header, so the browser thinks it's text.

inb4 "Bungie in charge of working internet service"

Anyhoo, if you use it in an <img> tag, most browsers take that as a sufficiently strong hint that it's actually an image and they should ignore the MIME type and try to work out what type of image it is.

>>29775
it's a gif (gif89a) according to the start of the text.