Spell Speeds

Spell Speeds is a core mechanic in Spell/Trap Chains in a Yu-Gi-Oh duel. They are used in regards to priority over one another.

Spell Speed 1
Spell Speed 1 is the slowest Spell Speed in the game. This Spell Speed is caused by a Monster's Flip Effect, Continuous Effect, and Ignition Effect, and Field, Equip, Continuous, and Normal Spells. You may not chain Spell Speed 1 effects to others, unless it's the case of say "Shining Angel" attacking "Shining Angel", and you cannot chain TO a Spell Speed 1, only respond to it, such as a "Trap Hole" for a monster summon.

Spell Speed 2
Spell Speed 2 is the second Spell Speed. All Continuous and Normal Trap Cards are Spell Speed 2. So are Quick Spells, and Quick Effects of some Effect Monsters. You may use Spell Speed 2 cards either to respond to Spell Speed 1 cards, or chain to other Spell Speed 2 cards, causing a chain, with the last card resolving first, and going backwards in the chain respectively.

Spell Speed 3
Spell Speed 3 is the fastest Spell Speed in the game, and the only cards with Spell Speed 3 are Counter Traps. This cards may respond to Any Spell Speed 1, 2, or other Spell Speed 3 cards. It is important to note that if the last card in a chain is a Spell Speed 3 Counter Trap Card, then you can only chain to that Counter Trap with another Counter Trap Card, so you could not chain Mirror Force to Solemn Judgement or Dark Bribe.

Important Last Note
Regarding Chains, if a monster attacks, and the monster's attack is chained to by a card like "Mirror Force" and the opponent uses "Dark Bribe", once "Dark Bribe" resolves first in the Chain negating "Mirror Force", then you may not chain 'Sakuretsu Armor" to the original attack the chain was caused over, because then you would have to chain to "Dark Bribe", which "Sakuretsu Armor" cannot chain to, meaning that the attack would go through, and you would have to wait to start a new chain against a different monster.

Another fine article.

I would have liked you to show a few examples of things where spell speeds 'work' and where spell speeds 'don't work' (such as the example in the last section) just so people don't get confused. 8/10 for this one.