The act of doing things for other people.  Then I heard the terms:

Internal Revenue Service,

Postal Service,

Telephone Service,

Service Stations,

Customer Service,

City/County Public Service,

Government Service,

And I became confused about the word "service. 
Then one day, I overheard two farmers talking, and one of them mentioned that he was having a bull service a few of his cows.

SHAZAM!! It all came into perspective.  

Now I understand what all those "service" agencies are doing to us...