Answer:
The simile and the metaphor are two <u>literary figures</u> that have in common the fact that they are used to make a comparison.
That is, both compare two words, concepts or terms, but the difference is that:
While the <u>simile</u> links two terms with a comparative nexus (such as: <em>as, similar to, it seems, just like</em>, etc.); the <u>metaphor </u>does not, because in this case one term represents and substitutes the other (terms that are different but share some type of similarity).
For example, the following sentence has a simile:
<h2>Her eyes were <u>as</u> green as emeralds
</h2>
Here we are making a comparison using the <u>comparative nexus</u> as.
And this one is a <u>metaphor:</u>
<h2>
I was lost in her <u>emerald gaze
</u></h2>
Here we are making the same comparison (the green color of the eyes with the green color of the emeralds). Nevertheless, no comparative nexus is used.