Twitter's stock has nearly doubled in the last six months, against a 11% rise in the Nasdaq Composite.

So far in February, while the Nasdaq lost as much as 10% of its value during last week's selloff, the stock traded up 22%. The mighty FAANG were tumbling alongside nearly everyone else, but Twitter held its head above the fray to reach its highest point in two and a half years.

What did Twitter do to win the favor of investors during a market slump? Why, it posted a profit! Net income in the fourth quarter swung to profit of $91 million from a loss of $167 million a year earlier. For all of 2017, Twitter's net loss shrank to $108 million from $457 million in 2016. If you've been following Twitter for the past few years, you recognize this as good news...