The Super Armor (スーパーアーマー), also simply referred to as "Armor", is a property that certain attacks in the Street Fighter series and other fighting games have.
Introduced to the main games in the Street Fighter III series, Super Armor grants the ability to absorb a single attack without being hurt or even being stunned. Such an ability is bestowed by certain EX Special attacks and, in the Street Fighter IV series, by Focus Attacks (where the manual refers to it as Hyper Armor).
When struck while employing Super Armor, the armor disappears, and a portion of the user's Health Meter is greyed out as provisional damage, instead of losing it outright. The health meter recovers gradually to what it was, with health slowly filling the grey segment if the player is not hit again; however, if the player is hit and suffers damage, the amount of health represented by the grey segment which has not yet recovered is permanently lost, as well as whatever other damage the second attack inflicts.
Multi-hit attacks can interrupt the player's attack by depleting their armor and then hitting the now unarmored character. Throws and Command Grabs (as they are not physical strikes) will ignore Super Armor, and Armor Breaking attacks will not only destroy the player's armor, but deal more damage and stun then the attack would normally have.