Differences between trades and quote, NYSE Data

Hi,

I have a question concerning general trading:

What is the difference between "Trades" and "Quotes"?

My question comes from the Nyse trading systems.
If you look here:

http://www.nyxdata.com/nysedata/DataProducts/NYSE/CustomTAQ/tabid/731/Default.aspx?rfrby=glry-794

you will see that Nyse Technologie makes a difference between trades and quotes.
I guess that is a terminology of NYSE systems, but I think it applies in a more general frame.

I guess that all trades are not quotes, but some quote are in fact real trades.

Do you know the difference? When does a trades becomes a quote?

Thank you

 

Trades are usually just what it say, that is trades. Quotes are usually bid/ask prices (with size).

 

I mean to say "best bid / best ask" - the first level of the order book (market depth).