In emacs mode (switched by: set -o emacs) it's:

• Ctrl+A and Ctrl+E.

In vi mode (switched by: set -o vi) when in command mode (Esc) it's:

• 0/^ and $ (it'll stay in command mode)
• I and A (it'll switch to edit mode)

In emacs mode (switched by: set -o emacs) it's by pressing:

• Ctrl+A and Ctrl+E
• Home and End
• Esc+b and Esc+f (moves the cursor backward and forward of the current word )

In vi mode (switched by: set -o vi) when in command mode (Esc) it's by pressing:

• 0/^ and $ (it'll stay in command mode)
• I and A (it'll switch to edit mode)

See also:

• Advanced Shell Topics: Command line movement and editing