An article I was reading noted that more than half of all U.S. households are invested in our stock markets. In 1929, this figure was much lower. But, even in the early 1900s, businesses relied heavily on the markets for capital. And by the Roaring Twenties everyone seemed interested in the stock market.

The essay pointed out that in August 1929, just two months before Black Tuesday, John Jakob Raskob, the builder of the Empire State Building, published an article in the (oft neglected) Ladies Home Journal. The title of this article was Everybody Ought to be Rich, and Raskob described how:

If a man saves $15 a week, and invests in good common stocks, and allows the dividends and rights to accumulate, at the end of twenty years he will have at least $80,000 and an income from investments of around $400 a month. He will be rich.

Joseph Kennedy, the SEC's first chairman and father of the late President John F. Kennedy, reputedly told colleagues that he sold most of his stock prior to the 1929 Crash after his shoe-shine boy started giving him stock tips. He reasoned that if his shoe-shine boy knew something he didn't, something had gone seriously awry with the markets.

While economic circumstances may change, one basic investing dictum hasn't; "buy low, sell high". This may explain the increased number of articles foretelling the markets eventual correction.

Market wise, equities are in the midst of the second longest rally since 1929. Yet, according to some market soothsayers, there are warnings signs that ought to make us sit up and take notice.

They may not be as telling as your shoeshine boy, but for some, they are signs of the apocalypse. The dire warning signs can be found, not in the news, but in the euphoria that is spreading around corporate America and the hallowed halls of the investing community.

For example, media outlets like Fox plan to launch a new business channel. The Dow Jones Industrial Average reached an all-time record high and other indexes reached multi-year highs.

Penny stocks and small-cap stocks outperformed their mid and large-cap peers by a wide margin. Wall Street expects to pay out $23.9 billion in bonuses, a 17% increase over the previous year's record.

So, does all this joy and euphoria point to a serious market correction? You don't have to be a financial genius to know that the markets have, and always will, ebb and flow.

After all, the markets are made up of investors, and if investors want to leave the market, there is no way from keeping the market from dropping. However, most investors leave because of increased market volatility and nervousness; which is always present.

"Some selling is actually good for the market, there's less of a possibility for any panic selling if we do decline because they'll already be out of the market," said one market analyst.

Fear is what many think was behind the market crash on October 19, 1987, or Black Monday, as it is called. Fear of a correction. Fear of a drop. Fear of not being able to sell. On that day, the stock market plunged 508 points, or 22% of the total market value.

While it took a full 15 months for the Dow to return to its pre-crash levels, it's important to note that the day following the crash the Dow rose 102.27 points, its largest one-day gain ever.

According to a number of market analysts, the absence of fear and the presence of optimism mean the markets will continue to grow this year, and could even lurch forward if the Fed decides to cut interest rates.

What does a potential late-year lurch mean to penny stock investors today? Not much. But the ongoing euphoria in today's Bull Market ought to teach, or remind us that we shouldn't be careless.

A Bull Market does not mean we have a golden-touch when it comes to stocks. In fact, a bull market can give us a false sense of security. If there's one thing we shouldn't forget, it's the markets will always be risky.

Even in a bull market, as a penny stock investor, you want to "buy and sell"...not "buy and forget to sell". Risk is still there; it's just hiding under the "joyful sentiment of the bull market."

You can't buy at the "bottom" and sell at the "top" every time; not should you really be looking to. What you need to do is buy a great penny stock when it's undervalued, and sell it when it's fairly valued.

And that's something you can do whether we're in the midst of a bull or bear.