I am going to be taking Intro to Physics in the Fall when I go back to college. I've always been terrible in mathematics and have never taken physics before! I found a cool little website called physicsclassroom.com. In an effort to get a head start on what will most likely be my toughest subject, I have printed out Lesson One which reads like Greek to me. I am positive someone can answer this question though. Regarding acceleration, the tutorial states "In Example D, the object is moving in the negative direction (i.e. has a negative velocity) and is speeding up." I understand WHAT it is saying (i.e., I would be able to answer a question on a test) but I do not understand WHY, or HOW, rather, something can move in a "negative direction." To me, there is up,down, left and right -all of which are positives. If something is moving, it's going somewhere tangible. To move in a negative direction makes me assume it is going someone INtangible. Is the object going to Hell? Can someone give me a real-life example of something moving in a negative direction?