A lead is a person who has shown interest in your product or service and left their contact information. But don't confuse just viewing an advertising banner with a real lead, since without the ability to contact the user, it will be impossible to continue the interaction.
Leads are also those who have performed certain actions on a website or with advertising materials. For example, a user who added a product to a cart or clicked on a banner is also considered a lead, since he or she showed interest in the product or service.
It is important to understand that a person who simply wrote to the company does not yet become a lead. To do this, you need to leave your contact information so that the business can contact him and offer further cooperation. The exception is when a potential client personally visits a point of sale or the company's office.