Both of them prompt you to enter your name and email in exchange for some goodies.
Ever since I enabled that feature on my WordPress website by using a few free plugins I have started getting leads everyday
- Contact Form 7 by Takayki Miyoshi
- Contact Form CFDB7 by Arshid
- Popup Maker by WP Popup Maker
Search for these plugins on Google or your Plugins directory in the WP Dashboard and install them on your WP Website