....though I must take you to task on that, bobs mum - a "jack" is a flag flown from a "jackstaff" at the stern of a ship. I know most people called the Union Flag the Union Jack, but I am afraid that most people are wrong (unless it happens to be on a jackstaff!)
OH, wow -- sorry i did not know that --- no hard feelings at all, I thought that 'jack' was a generic term for a flag as is standard ---- thanks again, oh, i'm having an education