In language and communication, context is the part of an utterance surrounding a unit and which may affect both its meaning and its grammatical contribution. A context-free grammar is one where the rules apply regardless of context; a context sensitive grammar is one where this is not so. Context also refers to the wider situation, either of speaker or of the surroundings that may play a part in determining the significant of a saying.
Contextual meaning maintains that meaning is relative to a context which is seen in relation to certain features, like intentions and presuppositions of the members of a conversational situation. These features determine under what standards one’s claims are taken to count as meaning of a grammar. Therefore, there is the possibility that there are different meaning standards according to different contexts.
Consider the following example:
A: Will Mary get to work before noon?
B: Marry had left home.
Although ‘B’ does not literally asserts that Mary left home at a particular time, she does communicate as much. More precisely, ‘A’ could infer the communicated content by noticing that the asserted sentence taken literarily (‘Mary left home at least once in her life’), would be less informative than required in the context: thus, it would violate one or more principles of conversation (“maxims”) whereas there is no reason to suppose that the speaker intended to opt out of conversational cooperation. If the interlocutor assumes that the speaker intended him to infer the communicated context –i.e, that Mary left home that morning, so presumably she would get to work at noon –cooperation is preserved. Such non-asserted content is negated than expanded by the implicature.