や

from “A Dictionary of Basic Japanese Grammar”

1. a suffix attached to names of stores, inns, and Japanese-style restaurants or to persons engaged in certain occupations
   1. store
   2. can sometimes be used to downgrade a person - careful!
2. a coordinate conjuction that is used to list two or more items (nouns or noun phrases) in an inexhaustive fashion
   1. and
   2. this is for when you’re not listing everything. if you’re listing everything, use と