The Duolingo icon, Duo, is sick. It doesn't look like Tylenol or NyQuil can make Duo feel better. The only way Duo can heal is if you complete your lesson. As long as you leave Duo hanging, he's going ...

I spend a ton of time at the computer keyboard, typing consistently as I write post after post. But there are times when I like to get hands-on with another activity that I enjoy: playing guitar. Now ...