Observation is the action or process of observing something or someone carefully in order to gain information about them.
Observation in research can be classified as participant and non participant.
In participant observation, the observer or researcher becomes more or less member of the group under observation and shares the situation as visiting stranger, an attentive listener, an eager learner or as a complete participant observer registering, recording and interpreting the behavior of the group.
In other hand in the non participant observation the observer or researcher observe through one way screen and hidden microphone. The researcher remain at distance and look, register and record what is going on. he keeps his observation as inconspicuous as possible. The purpose of non participant observation is to observe the behaviour in the natural setting. The subject will not shift his behavior or the respondent will not be conscious that someone is observing his behavior.
The advantages and disadvantages of the participant and non-participant observation depend largely on the situation. Participant observation is helpful in studying criminal activities or situation which necessitate the researcher to have intimate knowledge about the group. It gives the researcher a better insight into how the group or respondents live and therefore it gives a more valid outcome.
The disadvantage of participant observation is that it is time-consuming as a researcher has to develop relationships with members of the group and there is a chance that the researcher will lose his neutrality, objectivity, and accuracy to rate things as they are.
Non-participant observation on the other hand is used in the situation in which the researcher can not interact with members of the group observed. This type of observation permits the use of recording instruments and the gathering of large quantities of data.