Question: I have never really understood the connotation of someone calling their domicile a *condo* over the word *apartment*. I have a vague feeling the former is fancier and more up-scale, but are there any real differences I'm not aware of?

Answer: 
In the US, a [condominium](http://www.merriam-webster.com/dictionary/condominium) involves an investment of funds, and is similar to buying a house. A person actually owns a condominium and can sell it for a return on investment. Also, they can use it as collateral for borrowing money.

An [apartment](http://www.merriam-webster.com/dictionary/apartment) is rented/leased from a landlord/landlady. Rental payments go to the owner, and the tenant does not own the property, so cannot borrow against it. When a person moves out of an apartment, they may receive their security deposit back, but that's about it.

I think owning a condo probably is considered more high-class than renting an apartment. Many, many rich people in New York City own condos, for instance, and brag about it.
Condos tend to be in complexes rather than single buildings. Additionally, a condo is purchased and owned, whereas an apartment is rented.

[This Link](http://www.realtor.com/Basics/AllAbout/HomeAffordability/Condo.asp) has some good info about condos.