I never thought I'd run for president. My parents were immigrants to this country - and leader of the free world was not on the list of careers presented to me as a skinny Asian kid growing up in upstate New York.

When I was growing up, I'd study for days trying to get good grades. When I'd get an 'A,' I'd feel elation for about 30 seconds, and then a feeling of emptiness.

You will almost always leave a professional services environment with a few noteworthy friends and relationships. These contacts can prove to be extremely valuable both personally and professionally.

Tell young girls they can be anything, including entrepreneurs and self-made billionaires. Encourage your friends/daughters/female students/yourself to take a shot.

I'm also the chairman of the board of Symantec, which is the world's largest cybersecurity - software cybersecurity company.

As big a problem as gun violence is for Chicago, it is not beyond our ability to solve. Ending this string of tragedies is our top priority as a city. We are infusing our police department with the manpower, technology and training to meet this challenge head on.

The reason people need advice on using social media is that they're a much more complex and nuanced way to communicate than a conversation or email.

As the father of six children, I know very well the challenges technology poses to our families.