Locking eyes with someone and letting the moment linger – does that count as flirting? How about exchanging compliments on each other’s Instagram photos? 

And if flirting is defined as behaviour which suggests you are sexually attracted to someone – but stopping short of saying it outright – is it a form of cheating if you are spoken for?

This is a question that increasing numbers of people have been searching for the answer to in recent years, according to Google Trends. And the debate is also being fought out on social media.

To some, behaving flirtatiously – be that in person or on a device – is out-and-out wrong. If you are invested in your partner, your eyes shouldn’t wander. 

For others, flirting is healthy and natural as long as it doesn’t lead to anything physical.