My Professor frequently uses the term higher dimensions. Could someone tell me exactly what is a dimension. I think of it as some parameter which can vary. Also, I only know of 4 dimensions: time, length, width and height. Could someone give me more examples of dimensions? And lastly could temperature be taken as a dimension, I mean if my (above) notion of a dimension is correct then temperature is adimension as it tis a parameter/quantity/entity/something which can vary.