Defense
Blocking
Blocking is performed by holding away from the opponent (
or 
) and will guard against the opponent's attacks. Blocking cannot be performed while airborne or during the recovery of your own attacks.
Most attacks can be blocked standing or crouching (/). Overhead/High attacks must be blocked standing , while Low attacks must be blocked crouching .
Crossup attacks occur when a move hits behind an opponent, usually during a jump-in (usually j.LK or j.MK). These must be blocked by holding forward (
) as though attempting to walk underneath the opponent. Crossups cannot connect on a fully cornered opponent, and can be blocked in either direction. If a cornered character blocks by holding back, the jumping character will land in front; if blocked by holding forward, they will land behind the opponent in the corner.
Auto Guard: when a character is stuck in a "true blockstring" (never exiting blockstun between attacks), they will automatically block mid and overhead attacks even without inputting a block direction. Low attacks must still be blocked low, and overheads will not be successfully auto-guarded if the player holds crouch block. True blockstrings are rare except when the blocking character is in Burnout, as even chained light normals have a gap between hits when blocked.
Proximity Guard: holding back during the startup of an opponent's attack will cause the defending character to enter a blocking animation before the move actually connects. Compared to previous SF games, it has been severely toned down; in general, proximity guard will not be triggered from outside the attack's usual range. Projectiles also have reduced proximity guard activation range, making slow fireballs less effective at controlling the opponent's positioning. Proximity guard still has an impact in neutral, making it harder to walk back out of an opponent's poke range at the last possible moment. Slow, long-range attacks like Drive Impact and some heavy command normals are still very effective at preventing the opponent's back walk during startup.
Throw Techs
By pressing 
+
(LP+LK) shortly after a throw connecting, you can tech a throw. Teching a throw causes you to push the opponent away, preventing any damage and returning both players to neutral. Only regular throws can be teched; command grabs and air throws cannot. Throws that are connecting as a punish during the opponent's recovery cannot be teched. You can input a Throw Tech until the 9th frame after a throw connects.
Drive Parry
Drive Parry can be used to parry opponents attacks at the cost of drive resource. Drive parry can be done by Holding 
+
(MP+MK). Parries can block high/low and left/right while the buttons are held, and results in the same frame advantage as blocking the attack. You also build significant Drive gauge; if you bait the opponent's wakeup Super Art, you can refill your Drive almost entirely just by holding Parry instead of blocking. If perfectly timed, a parry will become a Perfect Parry, allowing for powerful punishes.
More details about Drive Parry can be found here
Wake-up
There are two types of wakeups in Street Fighter 6: Normal Rise and Back Rise. There is no difference in the knockdown frame advantage, so meaty setups are unaffected as long as the opponent remains close enough to attack. Holding or inputting 2 buttons upon landing will result in a Back Rise—otherwise, a Normal Rise occurs. Hard Knockdowns (such as a Throw that connects as a Punish Counter) prevent Back Rise entirely.
Characters count as standing for one frame on wakeup, even if holding crouch. Meaty attacks that only hit crouchers will still hit. However, waking up with a crouching attack will cause the character to skip this standing frame.
Reversals
Inputting a Special Move or Super right before wakeup or before exiting hitstun/blockstun allows the move to be buffered as a Reversal. This makes the move easier to time defensively. The most useful reversals are moves with invincibility, as they can beat attacks that are hitting "meaty". Only OD Special Moves and Supers can have true invincibility on startup, but not all of them do.
There is a 4 frame buffer when performing a reversal on wakeup or out of hitstun, blockstun, or air reset. This means that you have a 5 frame window to time the reversal on the first possible frame that you are able to act. This also applies to things like normals, throws, or Drive Impact, but buffering Drive Parry will not allow you to get a Perfect Parry. Dashes are supposed to have a 7 frame buffer period, although this is not universal; for example, the buffer is still only 4 frames after blocking Ryu 5MP (which may be an unintended bug).
Armor
Drive Impacts and some special moves (e.g. Luke 236KK) can absorb attacks with a property known as "armor". This only works against strikes and projectiles; any Throw will beat an armored move. Some moves, like Super Arts and Drive Reversals, also have an Armor Break property that prevent armor absorption.
When absorbing an attack, the character takes 50% of a moves normal damage as recoverable damage. represented by part of the health bar turning gray. This means that armor is not useful when at low health, since a KO will occur. Many players will instinctually try to counter a Drive Impact with a DI of their own, not realizing that they don't have enough health to survive the armored hit. While these weaknesses makes it a bit weaker than true invincibility, armored moves can still be a useful tool in your defensive playbook.
Anti-Airs
An Anti-Air is an attack used to interrupt an opponent's jump attack. This is usually done with a normal, special, or super that hits upwards like an uppercut. Many specials like Ryu/Ken's Shoryuken, Guile's Somersault Kick, or Kimberly's Bushin Senpukyaku have invincibility frames against airborne attacks, making them particularly useful as anti-airs. (Note: these AA Invuln moves also work against airborne attacks like Chun-Li's 6HK, but many attacks that appear airborne actually are not, like Guile 6HK).
Not all characters have useful anti-airs at every range. Other techniques for countering air attacks include jumping with a quick air attack of your own (known as "air-to-air). This is most effective when done with a fast light normal, an air normal that causes a knockdown, or an Air Throw.
Against close jumps, walking under the opponent may cause their attack to whiff, which can open them up to a Punish Counter during their landing recovery frames. It is also possible to Low Profile some air attacks by using a move that shifts your hurtbox very low to the ground.
Some air attacks can alter the trajectory of a jump-in, making the character more difficult to anti-air consistently. In general, attacks like this are put into a "Forced Knockdown" state if they are hit while airborne, which makes it more rewarding to interrupt these attacks.
Punishes
When practicing punish combo routes, it's important to remember that your first attack will have 4 extra frames of hit advantage. This can potentially open up far stronger combo routes than are normally possible. In many cases, light normals are designed to only combo into weaker versions of special moves or a low-damage Target Combo. By linking into a longer range medium/heavy normal or canceling into a slower launching special move, the damage potential is much higher.
