Cantrians have the ability to create notes instantly without any tools or resources being required. Notes are weightless so a character can carry a pretty much unlimited amount of them. They also cannot be used as an ingredient for any project and used to be indestructible. However, it is now possible to delete "editable" notes, see below.
Creating and editing a note
To create a note, click on the button that has a picture of a hand holding a pen.
This will bring up the edit stage. A title is optional since note titles are generally surrounded by two hyphens on each side, so you would still see those even if the title was blank. It's generally good to use short titles that won't stretch on to several lines.
Next to the title area there is a button for uploading a picture
which is pretty self-explanatory. It is possible to use pictures hosted outside of the Cantr servers, but that is discouraged, as it can lead to missing pictures if the hosting service used deletes them.
Then there is the text area where you write the primary contents of the note. Multiple spaces and tabulators will be visible (although if you hit tab while editing the note, it will switch focus out of the text area so if you want to have some lines indented, it's best to write it in notepad or other plain text editor and copy-paste into the form).
The game will enter a line break after each row when displaying the contents of the note. This should be noted when you are including HTML tags because their length will also count even though they are invisible. HTML is allowed but you should not link to things outside the game. It should only be used for formatting text.
The capacity of a note is limited to 65535 characters. Unfortunately you only notice it from text missing from the end of the note after saving it. (Text that goes over the limit gets cropped.) So when writing long notes like diaries, it might be wise to continue on another note before you end up losing text.
Once you're done writing, remember to click on Store. If you use the back button then no note is created (or in the case of editing an old note, the contents are not changed).
Above the Store button you will see two radio buttons labeled "editable" and "not editable". It defaults to editable which means you or who ever picks up the note can edit the contents later on. If you set it to "not editable", after that you cannot add, change or remove any text. So if what ever you're writing is subject to change (like for example a diary or a citizens' list), you should leave it editable.
Dealing with existing notes
Notes can be picked up, dropped and dragged like regular objects. They can also be read with the eye button and copied with the copy button. While in the inventory, notes can be edited, provided that they haven't been set "not editable" and they can be inserted into envelopes. If you have several notes to handle, you can click on the button "Operations on several notes", which allows selecting several notes and dropping, putting them in an envelope or handing them to another character. Unfortunately the button is located beneath the list of notes and envelopes, so people with slow connections might have trouble accessing it if they happen to be carrying several notes - and usually if you need the button that means you are.
Currently only notes that are set to be "editable" can be deleted. To accomplish this, edit the note and remove all text and also the topic of the note, and save it.
As per March 2015 there was more than 500.000 notes in the game.