I work as the sole web developer in my department doing back end work. As I'm sure many of the developers here will attest to, a large portion of the time spent programming is spent on thinking how you're going to write the next class, function, etc..
I have a co-worker who is not savvy in software development who takes notice when I am not touching my keyboard. He often walks by my office and sometimes comments on how I should ask for something to do from my superior if I'm not busy. I often tell him that I actually am busy, but as my monitor is turned away from my office door. He is always incredulous.
While I can understand how it may seem that I'm watching videos or something by not actively typing for long periods of time, these comments are starting to get annoying. Frankly, I think he should mind his own work since I don't report to him in any way.
How can I politely deter his comments?