On Steemit you can publish your content using either the Markdown and HTML. Both are ok, and some people think that the Markdown is easier as it requires less symbols to type. The formatting of your text can be easily done only with the editor, it will turn the same.
These are only some major things.
# H1 title ## H2 ### H3
[link for google](https://www.google.com)
![image alt text description](https://i.imgur.com/8S9sRuBs.png)
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