THE SAME FREE TRIAL CHESS PUZZLES I DO DAILY HAVE LED ME TO THIS MOMENT

What does "Tr.T." mean in the third column on the fide ratings chart?

Can someone explain why is this a brilliant?

Black to Move, Can You Find M5?

Found this mate in 5 in a recent game.

Pinned pieces pinning pieces for the win

Almost missed a mate in 3

Poison Pawn Tactic that Won the game, happy hunting.

Shouldn't this be a blunder?

Got him

Is This Position Winable? White To Move.

Could my opponent have castles in this position? (I moved knight from g5)