Leave blank lines between paragraphs.
You can render text in italics or bold.
To write italics, enclose the text in double single quotes.
To write bold, enclose the text in triple single quotes.
To insert program source without reformatting in a monospace font, use three curly braces:
10 PRINT "Hello, world!" 20 GOTO 10
For more information on the possible markup, see HelpOnEditing.