Nasdaq Stock List Stock Exchange - NYSE/AMEX & NASDAQ?

Stock Exchange - NYSE/AMEX & NASDAQ? - nasdaq stock list

Hello, I am a novice in the stock market, and the following questions.
What is the difference between NYSE / AMEX and NASDAQ?
I know, NASDAQ is an automated system so you / buy sell stocks automatically. But what does it mean, listed from the NYSE and Nasdaq, is not what we negotiate the same population, no matter what? If I purchase / sale of shares (eg FBTX - New York Stock Exchange) to the account online brokers say tdameritrade that means I am negotiating with the automated system, if so, is at the NASDAQ? Confusion.

My second question is: I have an answer as to whether the stock NYSE / AMEX and NASDAQ stock based on its symbol,
1,2,3 Letter - New York Stock Exchange and NASDAQ 4 letter was, however, why the action FBTX NYSE?

Please help. Thank you.