Every time a person sees, feels, hears or smells anything about your brand it will make an impression on the person. It will tell a story about your brand. These events are called touchpoints. The sum of all touchpoints a person has with your brand is the experiences the person has with your brand. If it is a good experience and it creates good feelings for that person, your brand might gain that person one day as a customer.
The above graphic that looks like a sun is an illustration of (almost) all possible touchpoints people can have with a brand. The job of a brand manager is to control as many touchpoints as possible.