Public

A public radio station is a radio station that recieve all fundings from the public and different sources such as, licence fees, indicidual contributions, public financing and commerical financing.

A public radio station is something that is intended for the public and will benefit rather than for purely commericial concerns.

The BBC have 16 different national radio stations which is each targeted towards a specific target audience.
Some examples of the different radio stations from the BBC and their market are:

BBC1 plays popular music which is mainly aimed at a younger audience.
BBC3 plays classical, jazz and world music, with culture and drama. This is mainly aimed at the older audience. 
BBC5 Live is for sports and news, which a lot of men would enjoy more.
BBC6 Music is aimed more for people that enjoy rock and alternative music.