Industry, Profession, Job?

in part as response to nonsense like this "Twitter is one that can be difficult to understand the benefit of sometimes - for the recruitment industry simply rolling out job after job is incredibly boring"  Rectruitment is NOT an industry

Twitter is not an Industy....

or this

The Social Media industry is growing in New Zealand. We might be a few years behind the rest of the world... Social Media is not an Industry (although like most of the not industry industries you need to be industrious).
Real Estate - not an industry
Car Sales - not an industry
Working in a Recruitment - not an industry

Banking - Industry
Insurance - Industry
Tourism - Industry
Film and TV - Industry
Music - Industry
Building - Industry
Advertising - Industry

Teaching - Profession
Lawyer - Profession - the 'legal system' however an Industry
Television presenter - Profession
Musiscian - Profession

Job
Working in a warehouse
working in the #cubefarm
Working on a helpdesk.
Working in bank.
Working at an advertising agency.
Working in a store.