Ageing and Longevity

What is ageing?

So many words and phrases come to mind. What does ageing mean to you?
Perhaps you think of the word ‘longevity’, or ‘longevity research’ which is everywhere at the moment and becoming somewhat of a buzzword and phrase.
Perhaps you think of what happens with age, from the more obvious physical changes on the outside, or perhaps you think of the less obvious and more subtle changes that cannot be seen but are happening inside our cells.