# Zettel ID

A Zettel ID is an unique identifier that refers to a particular zettel. By default, neuron will use random alphanumeric IDs of length 8. But you may specify your own as well, as long as it contains only the following characters:

• alphabets
• digits
• hyphen (-)
• underscore (_)

## Why prefer random IDs?

Why does neuron use random alphameric IDs by default? Because then you are not forced to think of a suitable slug when writing a new note. A note’s title may change in future, so could a slug. Generally text editors make it easier to work with this, by automatically showing the title of the linked note next to the link (see Editor integration).