There's a reason cats rule the internet. No matter how terrible your day, a goofy feline post on social media can make even the most hard-hearted smile at least a little.

From silly to stoic, here are a dozen photogenic cats that were a hit on Twitter. Take a look and try not to grin.

https://twitter.com/SirowSirow/status/807859439743156224

Mary Jo DiLonardo writes about everything from health to parenting — and anything that helps explain why her dog does what he does.