Bullish short-term trading
If a short-term trader is bullish, they believe a stock will go up in the coming days, weeks, or even minutes. This may be based on analyzing stock charts or intraday volume and price action. In these cases, the bullish viewpoint may have nothing to do with the underlying company. For instance, if a trader believes a stock is oversold, they may buy shares in the hope of a quick reversal.
Other short-term traders are bullish because they're betting some near-term event will happen in a favorable manner. For example, a trader may buy a stock the day before its quarterly earnings are released, hoping that the company will beat expectations.