Repetition is the simple repeating of a word, within a sentence or a poetical line, with no particular placement of the words, in order to provide emphasis. This is such a common literary device that it is almost never even noted as a figure of speech. It also has connotations to listing for effect.
litotes - From Greek litos, "simple, single," it refers to an ironical understatement (e.g. no small amount) or two negatives.
used to make a positive