Assay or essay

VS. VS. The main difference between Essay and Assay is that the Essay is a piece of writing often written from an author's personal point of view and Assay is a investigative (analytic) procedure in laboratory medicine, pharmacology, environmental biology and molecular biology.

The measured entity is generally called the analyte, the measurand or the target of the assay. The assay usually aims to measure an intensive property of the analyte and express it in the relevant measurement unit (e.g. molarity, density, functional activity in enzyme international units, degree of some effect in comparison to a standard, etc.).

You might also know that essay can be a verb, with its most common meaning being "to try, attempt, or undertake": A very close approach to the evil of Idi Amin is essayed in Giles Foden's 1998 novel The Last King of Scotland, whose narrator is the Scottish personal physician to the dictator.

An essay is, generally, a piece of writing that gives the author's own argument — but the definition is vague, overlapping with those of a paper, an article, a pamphlet, and a short story. Essays have traditionally been sub-classified as formal and informal.