Understanding A Chain

I know some of you, heck maybe all of us have troubles with Chain/Cost/and Resolutions. I'll start by explaining the basis of a chain and the speed of cards.

Normal Spell Cards:
These cards are Spell Speed 1.
Examples: Dark Hole, Monster Reborn, Level Down
These are cards that normally start a chain, however, that all depends on the way things are done during the duel.

Quick Play Spells/Normal & Continuous Trap Cards:
These cards are Spell Speed 2.
Examples: Book of Moon, Mystical Space Typhoon, Trap Stun, Royal Decree
These are normally the second link in a chain or start a chain as well. (In fact, whatever card was activated first, is the start of the chain.)

Counter Trap Cards:
These cards are Spell Speed 3.
Example: Solemn Warning, Solemn Judgment, Divine Wrath
There cards are usually the best at stopping an opponent in their tracks. It really puts them in a bind.

Now to explain a few things:
Links - These are simply the cards used during a chain. Each new card activated during that chain becomes a link and gets a number.
Example: Dimensional Prison is activated, and Trap Stun is chained to it.
In this case, D-Prison becomes Chain Link 1 (CL1) and Trap Stun becomes Chain Link 2 (CL2).

Chaining - Notice how the different cards have different speeds. When chaining, you can only chain cards speed 2 or 3. Spell Speed 1 cards cannot be chained, they can be chained to, but can never chain. Also, when you are chaining cards, you can only chain cards of the same speed or higher. (This does not include Spell Speed 1 cards that can't be chained at all.) As started before, you can never chain down a speed.
Example: Chaining Up Speeds: Dimensional Prison (SS2) as CL1, Trap Stun (SS2) as CL1, and Seven Tools of The Bandit (SS3) as CL3. - In this chain, speeds are going higher, once you get to SS3, you can ONLY chain with a card that is SS3, NEVER SS2 or lower.

Now that you understand how a chain works, the next topic is going to talk about Chain Resolutions.

If you are confused in the slightest, feel free to ask questions and I will answer.