Facebook sometimes does this really neat thing where to show image preview of a link to in a status update. Its usually the website’s logo.
Basically, Facebook grabs it’s thumbnails from the original website page. However, sometimes you may get an option which photo you will choose to show it in a post but sometimes it does not give that option.
You can check whether your website logo is populating while pasting on Facebook using below Facebook debugger tool:
You need to add these meta information on your website for generating the image preview thumbnail:
<meta property="og:image" content="[image url]" /> <meta property="og:title" content="[website title]" /> <meta property="og:description" content="[website description]" />
There are some different ways which depends on how your site is built with. For example, some WordPress plugins are created for showing the website logo on Facebook post.