Example:

heading_h2_heading_h3_heading_h4 ===

More exclamation marks you use, the smaller the heading will be (up to 5 exclamation marks). Exclamation marks has to be exactly at the beginning of the line.

fruit_apple_granny_smith_orange_vegetables_garlic_onion

• Fruit
  • Apple
    • Granny smith
  • Orange
• Vegetables
  • Garlic
  • Onion

1. First item
   1. First subitem
      1. First subsubitem
   2. Second subitem