What are acrostic poems?

This alien loves stars.

She loves them so much that she wants to write a poem about them.

Stars up in the sky,

They sparkle with love,

All so glorious,

Radiant above.

She really really likes stars.

But this is no ordinary poem.

This is an acrostic.

So there is something special going on.

You see? That's the secret of an acrostic.

The first letter of each line spells out the word STAR.

Pretty neat eh?

Oh, ahem…