Investigation is a crucial element of the legal and law enforcement system. It involves a systematic search for the truth or facts related to a crime or a case. The word investigation has several synonyms, like examination, exploration, inquiry, inspection, scrutiny, and research. Examination refers to a thorough analysis or review of something to understand it better. Exploration is more focused on discovering and investigating new things or places. Inquiry and inspection are closely related to investigation as they entail questioning, observing, and analyzing to find answers. Scrutiny involves a close examination of something with a critical eye, while research is a systematic method of investigating an issue using data, methods and procedures.