The optimal price is the price at which a unit of a product can be sold at maximum profit under given market conditions.
In other words, the optimal price is the price point at which the seller is happy to sell their product, and your customers are happy to buy it. But in a market economy, the optimal price isn't some fixed figure. It is constantly changing under the influence of many factors.
Price points are the prices at which demand for a product remains relatively high. The demand curve is not a linear function. Searching for an optimal price resembles a wave sequence rather than a straight line. The crests of the waves are the price points.
The diagram below shows the price points marked as A, B, and C. When a supplier increases the price above a certain price (say, to a price slightly above the price point B), the sales volume decreases not proportionally to the price increase. This decrease is slightly more than the additional income from the increased unit price. As a result, the total revenue decreases when the company raises its price above a certain price.
Technically, the price elasticity of demand is low (inelastic) below the price point (steep part of the demand curve) and high (elastic) at a price above the price point (slightly inclined part of the demand curve). Companies, in the pricing process, find optimal price points and set them as the price.