Using the rich text editor you can format your text (e.g. a user story or detailed description) as you desire. Most of the format options displayed in the menu are well-known such as bold, italics, underline plus bulleted and numbered lists. For the advanced user you can edit the HTML directly in Source mode.
Inserting file references and images
You can upload attachments and insert references to them or (for images) display them inline. Simply click the image menu or the paperclip menu – or drag and drop your file into the editor. Inserted files/images will automatically be uploaded as attachments – and you can always insert/reference previously uploaded attachments.
References other stories or users
You can reference another story (or any other item with an ID) by writing # and start typing the title or ID. The editor will then suggest which item you want to insert a reference to. This reference will become a link to the item. Likewise, users and teams can be referenced by writing @ (however, this does not imply that the user is required to read the text as in comments).