Hi there, a metaphor is simply a comparison of two objects by equation. For instance, one might say, "she is a deer" in order to compare some woman to a deer. It is not to say that the woman is literally a deer, with hooves, a brown pelt and antlers—but the metaphor is used rather as an intellectual symbol to convey certain meanings, meanings that are often difficult to understand without some standards with which to compare them. We often think of deer being swift, nimble-footed, and shy of strangers, so this banal metaphor of ours is intended to relay the idea that the woman is also swift, nimble, and shy.
Instead of saying that the woman is a deer, we could have simply stated that she is like a deer—that is, we could have used a simile instead of a metaphor. In many cases, however, there are subtle ideas that the metaphor brings by extension to the subject.
In your example you are talking about the use of similes and Denis has given you many examples.