Shin Shoryuken (真・昇龍拳, True Rising Dragon Fist)
”You’ve just experienced the Shin Shoryuken! Tell me if you’ve seen any greater force!” 

The Shin Shoryuken is one of Ryu’s signature Super techniques, and of the four he’s known for, I’d say this is probably the one most people associate with him.

It debuted in Street Fighter Alpha 3, where it was extremely difficult to use properly- it has a great deal of startup lag, and even if you manage to connect with the first hit, if your spacing is not exactly right, the full move will not execute, resulting in the drastically weaker Kinjite Shouryuken (禁じ手・昇龍拳, Forbidden Rising Dragon Fist). Later games removed this extremely strict spacing restriction and designed the move to execute fully as long as the initial hit is not blocked. This also applies to the Shin Shoryuken’s “Satsui no Hadou” variant, the Metsu Shoryuken (滅・昇龍拳, Destructive Rising Dragon Fist).

Interestingly, the Alpha 3 version starts with a dashing elbow strike rather than a standard uppercut, perhaps reflecting that Ryu has not perfected the technique yet.