Google parent Alphabet reported that its profit in the final three months of last year climbed on growth in mobile search and video-sharing service YouTube. For earnings purposes, Alphabet separates operations such as self-driving cars and Nest smart thermostats into an "Other Bets" category, which nearly doubled revenue to $262 million in the quarter but still posted a loss of nearly $1.1 billion. Its main operating unit remains Google and advertising remained the money-making engine for the company.