Does +Spell Damage affect traps?

The hunter has 2 traps that deal damage (Snipe & Explosive Trap). I was wondering if those are affected by +Spell Damage like other spells.

And if they are affected, when does that happen? Does the spell damage of when you cast the secret lock into the card, or is it calculated based on the spell damage you have when the secret is revealed.

Spell Damage affects only cards that are of type Spell - they have a "Spell" label sticked to the bottom of the card, when you hover your mouse over it.

There are three types of cards in Hearthstone:

• Minion
• Weapon
• Spell

Traps, or more precisely Secrets, are Spells and are affected by Spell Damage, but in a slightly different way than usual. The bonus to damage dealt by Secrets is applied when it triggers, and not when it is being cast.

There are a couple visual cues in game that let you see which cards get affected by Spell Damage:

1. When you have a minion with +Spell Damage on the table, all the spells in your hand that deal some damage display the number of damage already increased by all the +Spell Damage effects currently active. Additionally the number is surrounded by asterisk (*).
2. When you hover your mouse over your minion with +Spell Damage on your battlefield, all the cards in your hand, that are affected by the effect, get highlighted with a purplish glitter for a few seconds.

Yes.

The bonus is calculated when traps are triggered. According to forum comments it worked like this at least as far back as October 2013. (unable to find any other comments or patch notes about a change)

Thanks to DakaPaka for help testing, albeit unknowingly.