A simile is a figure of speech that compares two things using the words "like," "as," or "than". It is a type of metaphor, but unlike a metaphor, a simile uses explicit words of comparison. Similes are used to create vivid imagery and to make surprising connections between two dissimilar things. They are effective because they "show" rather than "tell". Similes are commonly used in literature, speeches, advertising, and everyday speech. Some examples of similes include "as quiet as a mouse," "as strong as an ox," and "as fierce as a tiger". Similes should be avoided in formal contexts like academic writing.