Amazon (NASDAQ: AMZN) stock was an outperformer on Thursday, rising almost 2% higher against the S&P 500 index's 0.6% gain. Although Amazon is known chiefly as a direct-to-your-door retailer, the real powerhouse of its business is its cloud computing service. With that in mind, investors were cheered that the company isn't mixing it up in a fight that seems to be brewing between Alphabet and Microsoft.