No two cards can have the same name, but variants of the same name can refer to the same card, greatly simplifying handling of plurals, spacing, and punctuation.
A given name could technically have infinite variants. For example, "What", "What?", "What??", and "What???" are all variants. Teenage texters have demonstrated that this punctuation pattern may be pushed to extremes.
There are three special variants with special meaning: the canonical name, the link name, and the key.
Clicking on links to name variants will show the same card each time (you can try this out in the +example section). In each case the card will appear with its canonical name, meaning the full, official name that is stored in the database. The canonical name is set when the card is created or whenever the name is directly edited via edit > name in the menus.
Of the three name variants explored here, the canonical name is the most permissive in terms of allowing different characters. At the time of writing, the only three characters not allowed in canonical names are "/", "|", and "~".
The "name" views of a card will show its canonical name.
Link names url-safe name variants of canonical names. For example, if your card is named "What??", then the link name would just be "What". The question marks must be removed, because they have a special meaning in urls (they signal the beginning of a query string).
The link name preserves the canonical name's capitalization and pluralization; it largely just strips non-alphanumeric characters. (It also leaves asterisks and plus signs in place, because they have special meaning in Wagn).
The "linkname" views of a card will show its link name.
Keys are how Wagn determines which names are variants and which aren't. Technically speaking, names are variants whenever they have the same key.
Note that word breaks are significant. They can be represented in different ways (eg sea lion or SeaLion, which are variants), but words with different word breaks are not name variants (sea lion, sealion, and seal ion are NOT).
The "key" views of a card will show its key.