Markdown markup language is allowed in comments. I encourage you to follow these guidelines since it’s guaranteed the content will be rendered just fine.
A paragraph is simply one or more consecutive lines of text, separated by one or more blank lines.
Headers use 2-6 hash characters at the start of the line, corresponding to header levels 2-6 (h1 is reserved).
Markdown uses email-style > characters for blockquoting. You can hard wrap the text and put a > before every line, or be lazy and only put the > before the first line of a hard-wrapped paragraph.
Unordered lists use asterisks, pluses, and hyphens — interchangably — as list markers.
Ordered lists use numbers followed by periods. You can backslash-escape the period to avoid triggering a list by accident.
To produce a code block, wrap your code between three backtick quotes (`). You can optionally specify the language after the opening three quotes.
To write inline code, wrap your code between backtick quotes (`).
Horizontal rule tags (<hr/>) are produced by placing three or more hyphens, asterisks, or underscores on a line by themselves. If you wish, you may use spaces between the hyphens or asterisks.
A link is composed of a set of square brackets, containing the link text; immediately followed by a set of regular parentheses, containing the URL where the link points at (along with an optional title, surrounded in quotes).
Markdown supports a shortcut style for creating “automatic” links for URLs and email addresses: simply surround the URL or email address with angle brackets.
The image syntax resembles the syntax for links. Images consist in a an exclamation mark (!); followed by a set of square brackets, containing the alt attribute text for the image; followed by a set of parentheses, containing the URL or path to the image, and an optional title attribute enclosed in double or single quotes.
Markdown treats asterisks (*) and underscores (_) as indicators of emphasis. Text wrapped with one * or _ will be wrapped with an HTML tag (i.e. italics); double *’s or _’s will be wrapped with an HTML tag (i.e. bold). Strikethrough uses two tildes (~).