What are some games that introduced you to different genres for the first time?

JRPG - Pokemon Red

2D Platforming - Super Mario Bros.

FPS- Goldeneye 007

3D Platforming - Crash Bandicoot 3 Warped

Fighting - Street Fighter II

Racing - Mario Kart 64

Puzzle - Tetris

Simulation - The Sims

Sandbox - GTA III

Sports - NBA Live 97

Platformer - Donkey Kong

Fighter - Mortal Kombat 1

RPG - FF2 (US)

FPS - 007

Racing - Pole Position

Shooter - Galaga

Puzzler - Tetris (Gameboy)

Horror - Resident Evil 1 (Playstation)

Sports - Double Dribble

Sandbox - GTA3

Hard to remember tbh. I will make an effort but I have a very blurry memory from the time I was 6-8 years old

JRPG - Can be either Chrono Cross or FF VII
2D Platforming - I'm tempted to say Super Mario World, but my guts are telling me it was Donkey Kong Country. But maybe I'm crazy and the answer is actually Sonic 2, it all comes down if I either played first SNES or Mega Drive
3D Platforming - Crash Bandicoot 2 that's I'm sure
FPS - Medal of Honor
TPS - Tomb Raider? I think it's more an action game though
Fighting - The King of Fighters 96 or some Street Fighter although I can't remember which one. Marvel vs Capcom is also a likely answer
Racing - Carts was Mario Kart 64, realistic racing games was Need for Speed
Action Side Scroller - Some Mega Man X, don't know which one exactly. Metal Slug 4 is also possible. Also Captain Commando
Action 3D - Resident Evil 2 I think
Simulation/Manegement - Sin City
Real time Strategy - Age of Empires
Sports - Tony Hawks pro 2
MMMORPG - Grand Chase, but I personally see it more like an action adventure online. My true choice is Lineage 2

Platformer - Donkey Kong
Maze Game - Pac-Man
Shmup - Space Invaders
Puzzle - Quix

RPG - Wizardry
JRPG - Dragon Warrior (Dragon Quest)
Action RPG - The Legend of Zelda
MMORPG - Ultima Online

Adventure - Hitchhiker's Guide to the Galaxy
Action Adventure - Adventure
Metroidvania - Metroid
Roguelike - Shiren the Wanderer

FPS - Doom
Run N Gun - Contra
Third Person Shooter - Tomb Raider
Light Gun - Crossbow

Fighting - Karate Champ
Beat em Up - Double Dragon

Racing - Pole Position
Sports - Basketball (Atari 2600)

Strategy - Nobunaga's Ambition
Tactical - Shining Force
RTS - Warcraft
Simulation - Rollercoaster Tycoon
Sandbox - Rollercoaster Tycoon

Exercise - Dance Dance Revolution
Rhythm - Dance Dance Revolution
Motion Control - Wii Sports

Frank's Adventure - The day I lost my boyhood and realized there's more to gaming than just... gaming...

There are a few games that indirectly introduced me to new genres, for example:

Mario RPG was technically my first RPG in the traditional turn-based sense, although I had played several action RPG games or games with RPG elements up to that point like Zelda II, Faxanadu and Ys III.

Jurassic Park on SNES was technically my first time playing a FPS since the indoor areas were played from a first person perspective Doom / Wolfenstein style.

Body Harvest on N64 was the first open world / sandbox type game I played even before the original GTA.

And my first ever 1v1 fighting game even way before Street Fighter II was Karateka on Atari.  That game was awful lol.

RPGs: Dragon Quest, Ultima III

SRPGs: Final Fantasy Tactics

2D fighting games : Karateka

3D fighting games: Virtua Fighter

Racing: Pole Position

Platforming: Donkey Kong

FPS: either Battlezone or Koronis Rift

Shmup: Centipede

Action RPG/adventure: The Legend of Zelda

Metroidvania: Metroid

SRPG- Fire Emblem (GBA)

Visual Novel - Disgaea Infinite

Horror - Resident Evil 4

Music/Rhythm - Gitaroo Man LIves

Wrestling - WWF No Mercy

FPS-Halo:CE
TPS-Armed and Dangerous
3d platformer-Conker
Simulation-Sims
racing-Need for Speed
JRPG-Pokemon Gold
WRPG-The Elder Scrolls 3
Shmup- Galaga
action/adventure- Lord of the Rings-The Two Towers
2d Platformer-Super Mario bros
Fighting- Marvel vs Capcom 2
Sports game-NFL Fever 2003
Puzzle- Dr.Mario

Platformer - Sonic the Hedgehog

RPG - Final Fantasy VII

Shoot 'em up - Space Invaders

FPS - Doom

Action Adventure - The Legend of Zelda: A Link to the Past

TP Action Adventure - Tomb Raider

Fighting - Street Fighter II

Strategy - Total Annihilation

Racing - Super Hang-On

Puzzle - Tetris

Simulation - Theme Hospital

Sports - International Superstar Soccer Deluxe