The rim, also sometimes called the lip, is the open upper edge of the pot. Various styles of rims are possible, from the minimalist cut-like opening to elaborate compound ogee rims.
When thinking of your pots' rims, remember to take into account the use that the pot is likely to be put to. Sharp openings are uncomfortable for drinking, and elaborate ones will make your beaker into a dribble glass. If the function is to hold flowers or some other object, think of how the rim area will help the viewer's eye make the transition from the pot to the object it is holding.
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The neck of the pot, if there is one, also needs to follow its function. Certain necks are impractical for pottery that is to be used in the kitchen, for storage, or for any purpose that requires a hand to be able to reach its bottom.
The neck should also enhance the feeling you want to impart to your audience. For example, long thin necks tend to "read" as elegant, refined, and sometimes as prissy. Shorter, stout necks often give the user the feeling of sturdiness, stability, and strength.
The shoulder is the area in which there is a fairly obvious and sharp delineation between the neck and the body of the pot. If included in a particular pot, it becomes a strong focal point for the form and should be treated with authority. Tentative direction changes in this area of a pot will weaken the aesthetic feel of the entire vessel.
Not all pots have waists. As you would expect, when they are present, the waist on a pot is an area in which the form is collared inward. Pottery waists may consist of a strong demarcation between the upper and lower regions, or be a gentle concave curve between the outward swelling of the upper and lower areas it joins together.
The widest outwardly or convexly swelling area of a pot, especially if it is centered in the lower half of the form, is known as its belly. The belly, waist, and shoulder of a pot, taken together, are often known as the body of the pot.
Pots may or may not have a foot. When present, the foot is an area that is distinct from the body of the pot, and which is smaller in circumference than the body. The foot raises the pot up and away from whatever surface the pot is standing upon.
Feet are generally viewed as giving a pot more elegance and "presence"; visually they make the pottery form read as lighter. Tactility they can make a pot feel more comfortable in the hand if the pot is small enough for the hand to cup around its base. An overly tall, spindly foot can make a pot look and often actually be unstable.