While both terms - stock market and stock exchange - are used interchangeably, the latter term is generally a subset of the former. If one says that she trades in the stock market, it means that she buys and sells shares/equities on one (or more) of the stock exchange(s) that are part of the overall stock market. The leading stock exchanges in the U.S. include the New York Stock Exchange (NYSE), Nasdaq, and the Chicago Board Options Exchange (CBOE). These leading national exchanges, along with several other exchanges operating in the country, form the stock market of the U.S.

ECN/Level 2 quotes: ECNs, or electronic communication networks, are computer-based systems that display the best available bid and ask quotes from multiple market participants and then automatically match and execute orders. Level 2 is a subscription-based service that provides real-time access to the Nasdaq order book composed of price quotes from market makers registering every Nasdaq-listed and OTC Bulletin Board security. Together, they can give you a sense of orders being executed in real time.
B (Good) - The stock has a good track record for balancing performance with risk. Compared to other stocks, it has achieved above-average returns given the level of risk in its underlying investments. While the risk-adjusted performance of any stock is subject to change, we believe that this fund has proven to be a good investment in the recent past.
Buy in thirds: Like dollar-cost averaging, “buying in thirds” helps you avoid the morale-crushing experience of bumpy results right out of the gate. Divide the amount you want to invest by three and then, as the name implies, pick three separate points to buy shares. These can be at regular intervals (e.g., monthly or quarterly) or based on performance or company events. For example, you might buy shares before a product is released and put the next third of your money into play if it’s a hit — or divert the remaining money elsewhere if it’s not.