You may want to do things differently on repeat playthroughs of Mega Man X2. That's where these passwords come in. Less about simply starting the game at different points, these passwords can let you start at the beginning (after the Intro Stage) or near the end of the game with or without various collectibles and upgrades.
They won't save your lives, the contents of your sub tanks, or the Shoryuken, so you'll have to build those up again each time you load from a password.
All Sub Tanks, Heart Tanks, Upgrades, Zero Parts, Start at Final Stage
Skip right to the end of the game with everything except the Shoryuken.
All Sub Tanks, Heart Tanks, Upgrades, but no Zero Parts, Start at Final Stage
Great if you just want to try to fight with Zero.
All Heart Tanks, Sup Tanks, Upgrades, No Mavericks Beaten
For if you want to play through all of the stages but can't be bothered to hunt for secrets.
All Upgrades, Nothing Else
Start the game with all of X's upgrades but none of the heart or sub tanks.
All Zero Parts, No Heart Tanks, Sub Tanks, or Upgrades, Start at Final Stage
Fight the last two bosses severely underpowered.