Permanent

A permanent is a card or token on the battlefield. Permanents are typically at least one (and possibly more) of the following:
 * Artifact
 * Creature
 * Enchantment
 * Land
 * Planeswalker

A permanent need not necessarily be one of the above types. If a permanent somehow loses all of its types, it is still a permanent.

Permanent card
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Permanent spell
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Nontoken permanent
A nontoken permanent is every sort of permanent, except a token.

Non-permanents
Sorceries, instants, triggered abilities and activated abilities which can never enter the battlefield are often called non-permanents.

However some objects like emblems and counters are never considered permanents, even if they are on the battlefield.

The player themselves are also not a permanent.