Hi i wonder if there are any code i can put into my WP blogs when my visitors close the website a pop-up banner comes up with an great offer that they can choose to click on or just close. I tried to search but not sure what to search for. Thanks!
You'll want to check out the onunload Javascript event. Example: http://www.htmlcodetutorial.com/document/_BODY_onUnload.html
Personally I wouldn't bother launching a popup when they close the window or exit your web site. That was common years ago...so many web sites use to do that to the point that now everyone is numb to it. Screw the popup and focus on keeping your customers on the page with something engaging. Perhaps have a CSS overlay popup when they first ENTER the site offering a coupon. Then allow them to "minimize" it and have it collapse to the side so they can always access it again, if interested.