To say that space has three dimensions basically means that it is possible to draw three lines, each perpendicular to the other two. For example, one line from north to south,
… one from east to west, and the third up-down - but any other directions will do, as long as they are perpendicular to each other. As a result, you need three numbers to specify the position of an object in space, no matter what coordinate system you choose. To say that space has three dimensions basically means that it is possible to draw three lines, each perpendicular to the other two. For example, one line from north to south, one from east to west, and the third up-down - but any other directions will do, as long as they are perpendicular to each other. As a result, you need three numbers to specify the position of an object in space, no matter what coordinate system you choose. To say that space has three dimensions basically means that it is possible to draw three lines, each perpendicular to the other two. For example, one line from north to south, one from east to west, and the third up-down - but any other directions will do, as long as they are perpendicular to each other. As a result, you need three numbers to specify the position of an object in space, no matter what coordinate system you choose. To say that space has three dimensions basically means that it is possible to draw three lines, each perpendicular to the other two. For example, one line from north to south, one from east to west, and the third up-down - but any other directions will do, as long as they are perpendicular to each other. As a result, you need three numbers to specify the position of an object in space, no matter what coordinate system you choose. (MORE) 
