Everyone vs Everybody

Sometimes I do wonder how to use the English language correctly. These two words have always baffled me. So, while ‘watching’ (more listening to) the cooking programs on Sunday morning TV and starting composing/researching my PowerPoint/presentation for U3A Computer group for the coming Thursday morning, I stumbled over my introduction.

Do I start with: “Good morning everybody” or “Good morning everyone”?

I went online hunting, other people would say researching, for the usage of these two words.
I only needed to read 4 different sites when I found my answer.

Most sites informed me that
“both everyone and everybody share the same definition and that
many thesauruses usually relate the two pronouns as synonyms under any context.”

Choosing ‘everybody’ from ‘everyone’ can be rather difficult.
The difference is so minute that it is easy to be confusion.
The two words are now accepted by many grammarians as one as the same word.
Many sources either online or offline also consider using the two words interchangeably.
That is though not quite correct.

As I understand the definition:

  1. Everybody: the group addressed is considered as one single unit
  2. Everyone: each member of the group is considered as separate individuals