Can anyone explain the Coup Turc

The basic idea of "Coup Turc" is that you can't CAPTURE same piece (be it a draughtsman or be it a king) TWICE.
In real life games, when you perform capturing, you do jumps and only afterwards you remove captured pieces from the board, so that your opponent can observe jumping sequence.
"Coup Turc" can be considered as a measure for limiting the power of king in all "flying king" variants (International, Frisian, Russian, Brazilian, Pool, Spanish, etc.).
Only few draughts variants reject idea of "Coup Turc": Thai draughts (but it does diminish the power of king by mandatory landing on a square behind every captured piece), Turkish draughts. With regards to the latter, many draughts players dare to compare Turkish king to vacuum cleaner :)