What is Progressive JPEG and how to use it?

Hi All,

I want to reduce load time of my website. I’ve checked through Webpagetest.org and found that I’ve to use progressive images to reduce it but as I am not very techy guys I don’t know what is it and how to use it. Currently it showing 0/100 for that. So, please somebody help me to sort it out.

Any help would be appreciated.

My website is https://ipgwin.com