In places that have strong British influence, such as the US, Australia, South Africa, Singapore and New Zealand, the Thumb-Up gesture has three meanings: it's commonly used by hitch-hikers who are thumbing a lift; it is an OK signal; and when the thumb is jerked sharply upwards it becomes an insult, meaning 'up yours' or 'sit on this'. In some countries, such as Greece, the thumb is thrust forward and its main meaning is 'get stuffed!'
Never hitch-hike in Greece.
As demonstrated, when Europeans count from one to five, they use the Thumb-Up to mean 'one' , the index finger becomes 'two', whereas most English-speaking people count 'one' on the index finger and two on the middle finger in this case the Thumb-Up will represent the number 'five'.