Editing a segment can affect existing campaign?

Hello There,
What if we have a segment on which a email campaign is already running, and after some days we wish to edit the segment and add a few more data in that segment.
Will the campaign affect in this case? i mean will the people who were already in the segment earlier will get the emails from first? or only newly added data will get emails from first?

if you edit the segment, then the contacts in the segment will be affected.

Lifelike example:
You make a class reunion dinner in a restaurant where you invite everyone from year 2000, 2001 and 2002. (This is your segment.)
Everyone starts eating in the restaurant (campaign started) and when they just finished the salad, you change the segment so, that only year 2000 stays in the segment.
In this moment 2001 and 2002 leaves the segment, and with that the campaign too. So they will throw away they cutlery, leave their half eaten greek salad, stand up and leave the place.

Makes sense?