You won't find it on Google. It's a technique from a book for executives from the early 80's. The last chapter is on how to use a personal computer to manage your files instead of a file cabinet! No internet.
T.R.A.F stands for (T)rash (R)ead (A)ction (F)ile
The idea is everyday you, "along with your secretary" lol, Go through each item in your inbox and mark each item with either a T R A or F. You don't read or contemplate on the item you simply categorize it and move to the next item.
Mark T - to TRASH item like junk mail, unimportant, not worthy of a response
Mark R - to READ later ie articles, memos, letters, etc.
Mark A - to take an ACTION on this item. Phone call, pay a bill, etc
Mark F - to FILE this item away receipts, tax return, etc.
You are to do this exercise at the beginning of each day. The idea being your action pile is the items you need to work on. Schedule a time daily or weekly to go through your read pile and catch up on reading. Trash all the garbage and file away things you need to keep but don't need to look at.
Whatever you didn't complete from your action & read list you put back in your inbox for the next day. Each day mark a dot in the upper right had corner of the item. Once the item collects 3 dots. Force yourself to handle it that day. No more delay.
This system was designed in the days before computers but apply it to your email inbox and it works very well. I started by just using flags on the email messages. Green flag action, Blue Flag read, Red Flag trash, Orange Flag file.
I have since evolved into a custom system that is a blend of TRAF and Eiesenhower Matrix. I'm actually designing a mail client around this idea. It has greatly improved my ability to handle the onslaught of material that comes my way.