What the hell is Ease? I have embarked on a journey to discover just exactly it is. I have found some wonderful resources too that I wish to share below.
Ease ~ think of your skin as the neutral ease. If you try to put on an item of clothing and the sides rip out of it because it is too small you can say there is negative ease for your body verses the garment. On the opposite side if you put on a garment and it falls to the floor because three of you could fit in it that would be said to have positive ease. While these are extreme examples it helps me to think of it in terms I will remember. I am a black and white thinking by nature folks! Please don't hold it against me. :-)
So it makes sense that ease is an important consideration when knitting a garment. I have to admit I haven't paid too much attention to ease in my earlier knitting projects. Going forward I will have to be more aware so that I produce better fitting pieces for my body. IE be sure there is enough fabric to cover the girls rather than smash the girls.
Standards & Guidelines For Crochet & Knitting
Knitty Article