A grocer is a person who sells food and small household goods. Grocers were common in my youth and one could be found on every block of shops. Nowadays the supermarket rules and grocers are almost non-existent. Even the smallest block of shops has its mini-supermarket. Instead of the grocer, one might find the smaller rows of local shops include a newsagent or an off-licence which also sells a few groceries.
The title grocer comes from the word gross, meaning a large quantity (or, more specifically 144) and the original grocers were wholesalers rather than retailers.