You may find that certain characters do not show up as expected when typing on a keyboard connected to your Pi. This is because the default keyboard layout is set to work in Great Britain and some of the character mappings are different. To fix this you need to change the keyboard layout to work in the US.
To change the keyboard layout you need to edit a file. Type:
sudo nano /etc/default/keyboard
Change the line:
XKBLAYOUT="GB"
To:
XKBLAYOUT="US"
Save the file and reboot the Pi
sudo reboot