Lobbying in the United Kingdom
Formal procedures enable individual members of the public to lobby their Member of Parliament but most lobbying activity centres on corporate, charity and trade association lobbying, where organisations seek to amend government policy through advocacy. Companies and individuals who operate in this sector commonly use the terms "public relations", "public affairs", "political consultancy" or "corporate affairs" to describe their activities (though this was also a reaction to the negative publicity surrounding the word "lobbyists" following the 1994 Cash-for-questions affair). Professional public affairs agencies, representing multiple clients, undertake a significant proportion of lobbying activity in addition to individual organisations conducting lobbying on an in-house basis.
Mass communication
Public relations is the process of providing information to the public in order to present a specific view of a product or organization.  Public relations differs from advertising in that it is less obtrusive, and aimed at providing a more comprehensive opinion to a large audience in order to shape public opinion. Unlike advertising, public relations professionals only have control until the message is related to media gatekeepers who decide where to pass the information on to the audience.