You can add places for code to your site. It can be used for embedding Vimeo videos, Twitter or Facebook feeds, or other information directly from outside sites.
To embed code, click the Build tab and drag and drop the Embed Code element to your site. Go to the external website that has the code you want, copy and paste it into the box on your site. The box will show your viewers whatever the code represents, instead of the code. For example the code on the left will look like the Facebook Like Box on the right:
Here is a link to Weebly's Add Outside Content by Embedding Code