The difference between invisibility and eye to eye.
Explanation:
The difference between personal and online is simple.
Personal contact(s) are the people you think of as your real confidants, your go-to people if you need something, Meanwhile online contacts are the people you can only interact with when on your phones or laptops.
Also an online friend is someone you know is available every time you see that little green dot next to their name, so you write them and say hello.
