A page may be in read-only or read-write mode.
The page footer shows which mode you're in. For example:

Editing
The checkmark next to "wiki" indicates that you're in editing mode. Click the word "wiki" to toggle the mode.
A page may be in read-only or read-write mode.
The page footer shows which mode you're in. For example:

Editing
The checkmark next to "wiki" indicates that you're in editing mode. Click the word "wiki" to toggle the mode.