Stocks are considered cheap when their current price is much less than their underlying present value, based on assets and earnings, not future potential. Value is determined by analyzing book value per share, cash per share, working capital per share, and price-earnings ratio. While cheap stocks can remain cheap indefinitely, reducing risk involves identifying cheap stocks that have potential for price appreciation, such as those discussed in other videos and books on finding stocks with strong earnings growth or that could experience price increases after corporate events. Always do thorough research and only invest amounts one can afford to lose.