what is discourse according to Michell Foucault? and what is discourse analysis?lucid answer expected.please.

Discourse is the term New Historicists, in general, and
Michel Foucault, in particular, used to designate the system of thoughts, ideas and
images that encapsulate the concept of "culture".  Other terms have been used to convey
this concept but have failed to be accurate. For instance, traditional Historicists have
used the terms “ideas” and “concepts” to illustrate the flow of thoughts in a given
culture. However, those terms often deny the existence of representative ideas of
unprivileged groups in society, and the word “discourse” seems to be more suitable.
“Myth” and “Ideology” are other terms used by scholars, but then again, those terms seem
to be limited. The further has been largely misused and often gains different
connections. The latter is an ideal term that analyses power struggles within a society
but it primary brings about the ideas and thoughts of a dominant group or a class of
people. In view of that, one understands why the term “discourse” is suitable. It fits
the analysis of beliefs, opinions and viewpoints of all branches within a culture. The
term fully adapts to the idea that there are countless ways of seeing and talking about
the world. It recognizes the presence of many narratives, (discourses) that operate
simultaneously. In short, it rejects the discourses stemmed only from the ruler and
dominant classes, and instead it considers all types of discourses inherent from all
kinds of social groups and backgrounds.
 
There are several ways in
which discourse operates. First of all, being a chain of language, discourse allows
social communication; hence it plays an important role in the social construction of the
world. Second, discourse presupposes all forms of knowledge and truth. For example,
certain discourses in certain contexts have the power to convince people to accept
statements as true. Next, discourse reveals something about the people who say it-here,
discourse is not only a matter of language, but it is also about the person who speaks
it. For instance, through discourse one is able to identify the social class, gender,
ideology and ethnicity of the speaker. Lastly, discourse is usually involved with
recognized socially networks of power-discourses enable individuals with degrees of
social, cultural and even political power to be believed when speaking on special
subjects.
 
Thus, in brief, cultures are constructed by multiple
discourses that compete with each other, change over time and may be subdivided,
sometimes, into categories governed by specific rules.