When you take out a car battery, do you remove the red or black cable first?

Omg people are giving you different answers lol. No wonder this site is duped. 

Black off, then red to remove.

Black on then red to install. 

You can see where the wires go to.  One goes to the starter and one goes to the block or fender metal.  Take off that one first and put it on last.

British cars are opposite from MOST other cars. Positive is the ground.  Pay attention.  You will remember YOUR car after the first go at it.  It has NOTHING TO DO WITH BEING OLD, it was the decision of the manufacturer which is ground wire.  As the theory behind battery technology RAGES ON as to which way current flows.

You take off the ground/earth cable first. Unless your car is very old that will be the negative cable, which is invariably the black one.  It comes off first when removing the battery, goes on last when installing a battery.

It doesn't actually matter to the battery, it's purely a safety measure in case you happen to touch anything you shouldn't while using a tool.

Think football.  NFNL.  Negative First, Negative Last.

Always remove the negative cable first. Make sure everything is turned off to avoid sparks which can explode the battery which can accumulate hydrogen gas.

I always remove the negative first that way if you touch anything metal you don't blow up the battery.

Put the red on first when putting in a battery, remove the black first when you take out a battery, This reduces the chance of arcing.