Mainstream media (
MSM) is
mass media that influences a large number of people and both reflects and shapes prevailing currents of thought. It may be contrasted with
alternative media which may contain content more dissenting thought. Large news conglomerates, including
newspapers and
broadcast media, which underwent successive
mergers in the U.S. and elsewhere at an increasing rate beginning in the 1990s, are often referenced by the term. This
concentration of media ownership has raised concerns of a homogenization of viewpoints presented to news consumers. Consequently, the term
mainstream media has been widely used in conversation and the
blogosphere, often in oppositional, pejorative, or dismissive senses, in discussion of the
mass media and
media bias.