Combos (コンボ Konbo) is a succession of two or more hits while the opponent is in a "combo-state". In a combo-state, the opponent cannot retaliate. There are various types of combos.
An Airborne combo (空中コンボ Kūchū Konbo) is performed after a launch and while the opponent is airborne. The combo ends once the opponent touches the ground. The damage of each hit is gradually decreased with consecutive hits. With each hit, the opponent is hit further away until it becomes impossible to reach the opponent. At that point, the opponent will fall to the ground and end the combo-state.
Bound Combos (バウンドコンボ Baundo Konbo) are an extension of the airborne combo. Introduced in Tekken 6, the bound system allows airborne combos to be lengthened by the use of certain moves. These moves are referred to as "bound moves" and will bounce the opponent off the ground during an airborne combo for additional hits to connect.
Tag combos (タッグコンボ Taggu Konbo) utilize the tag system introduced in Tekken Tag Tournament. A tag combo is performed by launching an opponent and then quickly tagging out. If done properly, the tagged partner will arrive in time to continue the combo after the launch. This can be used to safely tag out a partner or perform more versatile combos. This can also be used at the end of an airborne combo instead to safely tag out a partner.
Tag Assaults (タッグアサルト taggu asaruto) are a combination of tag combos and bound combos. These were introduced in Tekken Tag Tournament 2. To perform a tag assault, press tag after a bound move. This will initiate the tag assault and your partner will appear. The opponent will bounce off the ground similar to a bound. Control switches to the partner and alternates as long as the opponent stays in a combo-state.
Ground Combos (地上コンボ Chijō Konbo) are performed while the opponent is on the ground. Prior to Tekken 3, when an opponent was knocked onto the ground, waking up would be sluggish.
Wall Combos (壁コンボ Heki Konbo) occur when an opponent is hit into the wall of a stage. If an opponent is hit into the wall during an airborne combo, additional "wall" damage will incur. Certain moves have special properties called wall splat, wall stun and wall bound. These are highly beneficial as cornering the enemy is an effective way of dealing massive damage.