These characters need to be escaped in Markdown in order to appear as literal characters instead of performing some markdown functions:
\ ` * _ { } [ ] ( ) # + - . !
Special escaping for hash (#)
You can usually escape a # with the \ character like others in the above list, but if your hash appears on the same line as an h1/h2/h3 which themselves start with #, ##, or ### then you need extra escaping for the inline #. In this case, add another # at the end...