[BobDDuck]

Long haul stuff is probably a bit different, but in general your take off fuel is built up like this

BURN (amount your engines will use to get you there)
+ RESERVE (standard reserve amount... 45 minutes of fuel domestically)
+ ALT/MISSED (fuel needed to go missed and go to your MOST DISTANT alternate)
+ HOLD (fuel used to hold)
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TAKE OFF FUEL
+ TANKER (extra fuel carried for what ever reason)
+ TAXI
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RAMP FUEL