As an oscillator , MACD oscillates around the zero line. When MACD value is positive , this might be regarded as a bullish (upward) market. When the MACD value is negative, this can be considered as a bearish (downward) market.
Another simple technical indicator that can be used by beginners in the stock market is the RSI oscillator. RSI (Relative Strength Index) is assumed to be first introduced by J. Welles Wilder in 1978.
The RSI indicator intends to quantify the strength/weakness of a certain stock based on its average closing prices.
Typically RSI is calculated using 14-day historical closing prices. The longer the average period is, the smother will be the behavior of the RSI line (similar to the behavior of a moving average).
The RSI is formulated such that it can have theoretical values between 0 and 100, oscillating around the value 50. When the value is higher than 50, it means that the gains of the underlined stock are higher than its losses. When the value is lower than 50, the losses are higher than the gains. In most practical cases the RSI will oscillate between the values 30 to 70. Technical analysts interprets RSI values such that when it increases and reaches the value 70, as an indication for the stock being too high (over-bought) and consequently an indication for selling it. On the other hand, when the RSI value decreases and reaches the value 30, this is regarded as an indication for sufficiently low stock price (over-sold), and as a trigger for buying the certain stock.
Simple as its behavior tends to be, ttfacilitates the application for end users.
More aspects of stock market can be found at Finance Library, Business Management Books and at Stock Market Library.