Price discrimination is where the same goods (or more or less the same goods) are offered at different prices in different markets and/or to different people.
Let’s say for example, that company A operates two coffee trailers one outside a private hospital and the other outside a public hospital. Assuming that the costs to sell the coffee are the same in both cases, if the prices are different then this is price discrimination.
If the elasticity of the consumers of these two “markets” are different, then the price discrimination can be successful.