You can share things you find around the Web with your Facebook friends, but you can also share things you find within Facebook.

Most Facebook posts have a line at the bottom, printed in blue, giving you the option to Like or Share the item.

When you click the “Like” button, it’s like giving it a thumb’s-up. The original poster and that person’s friends can see that you liked it, but that’s about it.

The “Share” button is much more powerful. It re-posts the message to your Wall, where all your Facebook friends can see it. It gives you the chance to say something about what you’re sharing. It’s a great opportunity to spread the word about important issues.

So, if you want to alert the maximum number of people, use the Share button!