Markdown is an easy-to-use, easy-to-read formatting language. It has writers in mind and is borne out of plain-text email communications.
For example, to create a level one heading, start a new line with the hashtag symbol
# then type the content of your heading. To create a 2nd level heading, use 2 hashtags
## and so on and so forth for up to 6 header levels.
Another example: to create bold text, surround the text with a pair of two asterisk symbols