I think a ghost or something was typing on my computer. It was writing about war and reacted to my voice. ?

ok since none of the virus answers are helping read this, you say you use the boards a lot, is it possible you forgot to close a session, ive read about other people leaving a session open, perhaps it got into your Computer and decided to tell you about its life, be open and creative. don't jump to conclusions and instantly say its not a virus or you'll spook yourself out. try reopening the session and saying something as simple as goodbye. or if your really that spooked say (or have a priest say) "leave in the name of jesus christ" if its a demon it may not leave still. seriousely DONT PLAY WITH THE BOARDS they are dangerouse