title: What does $- mean in Bash?
body: <p>I was playing around on the shell when by mistake, I typed <code>echo $-</code> and I got the result <code>himBH</code>. Immediately, I tried all other combinations of symbols along with the $ sign but with no luck.
  I read <a href="https://stackoverflow.com/questions/26793022/why-does-echo-1-output-this">this</a> post but I didn't fully understand it. Can someone please epxlain what they mean by 'shell options' and what himBH is supposed to mean?</p>
  
  <p>Much thanks!</p>