Which literary device involves a direct comparison between two different things?

A metaphor is a literary device that makes a direct comparison between two different things by stating that one thing is another, thereby highlighting similarities between the two. For example, saying "Time is a thief" implies that time, much like a thief, can stealthily take away moments from our lives. This direct comparison allows the reader to understand the concept of time in a more vivid and relatable way.

While similes also make comparisons, they do so using the words "like" or "as," which distinguishes them from metaphors. Analogy, on the other hand, is more about explaining an idea or a thing by comparing it to something that is quite different from it, often for the sake of clarification or explanation. Personification gives human characteristics to non-human entities, which does not involve a direct comparison at all. Thus, metaphor stands out as the answer when looking for a direct comparison between two disparate things.