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.
Competition has spurred many brokerages to slash commission fees, which can add up quickly if you buy and sell stocks, mutual funds or ETFs frequently. Robinhood is not the only company that does not charge commission fees. Starting in October, Interactive Brokers is providing an unlimited number of commission-free trades on U.S. exchange-traded stocks and ETFs along with no account minimums or inactivity fees.

Say, a U.S.-based software company is trading at a price of $100 and has a market capitalization of $5 billion. A news item comes in that the EU regulator has imposed a fine of $2 billion on the company which essentially means that 40 percent of the company’s value may be wiped out. While the stock market may have imposed a trading price range of $90 and $110 on the company’s share price, it should efficiently change the permissible trading price limit to accommodate for the possible changes in the share price, else shareholders may struggle to trade at a fair price.

Why I’m buying: Spell out what you find attractive about the company and the opportunity you see for the future. What are your expectations? What metrics matter most and what milestones will you use to judge the company’s progress? Catalog the potential pitfalls and mark which ones would be game-changers and which would be signs of a temporary setback.