A public medium of communication can be anything A roadside sign falls into this category A means of mass communication such as newspapers magazines radio or television is not limited to those mediums such as is the key here I spent most of my career in advertising isn t convincing Your opinion is based on your own experience in your own field but that does not necessarily mean that your interpretation of advertising is supported by the wider community Regarding you don t know what you re talking about please be civil Attacking the integrity of other editors is not affording respect