Rhetorical devices can be used to facilitate and enhance the effectiveness of the use of rhetoric in any of the four above modes of persuasion. Rather than certain rhetorical devices falling under certain modes of persuasion, rhetorical devices are "techniques" authors, writers or speakers use to execute rhetorical appeals. Thus, they overlap with figures of speech, differing in that they are used specifically for persuasive purposes, and may involve how authors introduce and arrange arguments (see the section on discourse level devices) in addition to creative use of language.