A customer login is a special type of user login that you can give to your customers. When your customers log in they will only see their own data. They can browse your product catalogue and submit orders and quotes but their login is restricted to only seeing their own information and seeing whatever products you want them to see. In addition, they cannot change any prices or discounts. You can give each customer multiple logins so that each staff member at the customer can get a separate login.
Related articles:
How customer self-ordering works
How do I notify my customers about their logins?