Cantrips are a special kind of spell that don't consume spell slots. This means you can cast them as often as you want, making them a spellcaster's go-to for consistent, reliable magic. They're generally less powerful than spells that require spell slots but can still be very useful.

Features of Cantrips:

1. No Spell Slots: Unlike higher-level spells, cantrips don't use up spell slots, so you can cast them freely.
2. Spell Level: Cantrips are considered level 0 spells.
3. Scaling: Many offensive cantrips scale in power as your character levels up, usually at character levels 5, 11, and 17. The scaling might involve rolling additional damage dice or adding other effects.
4. Spellcasting Ability: Like other spells, the effectiveness of a cantrip can depend on your spellcasting ability, affecting things like attack rolls or saving throw DCs.
5. Class Specific: Each spellcasting class has its own list of cantrips to choose from. Some classes, like Wizards, have a broad selection, while others, like Rangers, have a more limited range of options.
6. Versatility: Cantrips cover a wide range of utility, from attacking (e.g., "Eldritch Blast" for Warlocks) to utility (e.g., "Mage Hand" for Wizards) to defense (e.g., "Blade Ward").
7. Learning Cantrips: Most classes that have access to cantrips select a fixed number of them during character creation, and possibly more as they level up. Some classes, like Wizards, can also learn new cantrips from external sources like spellbooks, though this varies by class and DM discretion.
8. Components: Just like other spells, cantrips might require verbal, somatic, or material components to cast. However, because they don't use spell slots, they don't have the option for higher-level casting effects.
9. Action Economy: Most cantrips require an action to cast, but some can be cast as a bonus action or have longer casting times.
10. Range & Targets: Cantrips can have various ranges and target types, from touch to ranged, and may affect one or multiple creatures or areas.
11. Multiclassing: If you multiclass into another spellcasting class, you gain access to that class's cantrips based on the level you have in that class, not your total character level. However, the damage for all your cantrips scales with your total character level, not your level in a particular class.

Cantrips offer spellcasting characters reliable options for both combat and non-combat situations and are an integral part of the magic system.