to format your text, add images and links - you can now use the lovely Markdown syntax. The small editor icons will do half the work for you - but if you wish to explore other options ~ see this reference from Daring Fireball (John Gruber)
Had to miss a class? Forgot your notes or can't read your own handwriting? ~ this is the place to ask those 'silly' questions and to share useful bits :)
for best display of code - add it within these tags, specifying your quoted language.
for example: <pre lang="html"> <!-- your HTML code here -->
</pre><pre lang="css"> /* your CSS code here */
</pre>