Summary: February 2019 marks the 15 year anniversary of the social network. CNN's Laurie Segall explores how Facebook has changed how we connect for the good but also for the bad. The history is a complicated one and now begs the question: what's the future for this social network giant?

Summary: Fareed Zakaria explores a country where women are property, music and movies, evil - until a new Crown Prince bring unimaginable freedoms. But there is a dark side - is Saudi Arabia's new regime guilty of murder? Fareed focuses on the deeply troubled U.S.-Saudi relationship, from 9/11 to the current crisis.

Summary: For years, President Trump has bragged about his business prowess. However, he prefers to keep the details of how he makes money secret. Case in point: his current battles to keep his taxes and other financial documents away from scrutiny. CNN's Erin Burnett takes a look at how the Trump Organization makes money.

Summary: CNN's Kate Bennett explores who First Lady Melania Trump really is, from those who know her best.

Summary: White supremacy has become a crisis in the United States. The number of hate groups has soared to a record - over 1000 - and hate crimes are up by double digits. Fareed Zakaria traces the roots of the current crisis, looks at history to discover how racism becomes a political movement, and he interviews a White Supremacist in an effort to understand the forces driving the dangerous racial moment we find ourselves in.

Summary: From small towns in the Midwest to the President of the United States, Ed Lavandera travels across America uncovering the country's deep and contingent need for undocumented workers.

Summary: CNN's Poppy Harlow examines Amazon's journey from online bookstore to e-commerce giant and beyond.

Summary: CNN chief medical correspondent Dr. Sanjay Gupta goes on a nationwide investigation to look at the real-life impact of dozens of deregulations at the EPA. What does it mean for the health of American families?

Summary: The astronomically popular sitcom based in New York first aired in September of 1994. Alisyn Camerota takes a look back, and a look forward on what's to come of this hit that never really went away.

Summary: Anderson Cooper and Jake Tapper with the latest developments into the impeachment inquiry of President Donald Trump.

Summary: Anderson Cooper and Jake Tapper with the latest developments into the impeachment inquiry of President Donald Trump.

Summary: Those who know him and his environmental work best paint the picture of a Ted Turner often lost in the headlines, but no less important. Hosted by Dr. Sanjay Gupta.

Summary: More than six years since CNN's first investigation into medical marijuana, Dr. Sanjay Gupta searches for the truth about CBD, which has turned into a multi-billion dollar industry.

Summary: Fareed Zakaria looks at the frenzied competition for slots at elite schools - that has exploded into the biggest cheating scandal in American history - a scheme that exploited the desperate quest for higher test scores, as well as the world of elite sports, played only by the affluent, that college advisors call "rich white affirmative action."

Summary: Impeachment was meant to be a drastic, last resort measure - but in the last few decades, it has become a political weapon. Now that we find ourselves in the middle of an impeachment inquiry, we need to look to history, to understand how, why and even if we need to impeach Donald Trump.

Summary: CNN looks back at the two weeks of public testimony to summarize the impeachment case against President Donald J. Trump and lay out the secretive, months-long effort by administration officials to pressure the Ukrainian government to announce investigations of former Vice President Joseph Biden and alleged Ukrainian interference in the 2016 US Presidential election.

Summary: Chief Washington correspondent Jake Tapper speaks to scholars, historians, authors, and philosopher to explore the national impact of Trump's most egregious lies, and how in turn, he has created a culture of mistrust; leading Americans to question scientists, economists, world figures and the media.

Summary: The Salesians are a religious order whose reach and influence stretch through the highest ranks of the Catholic Church. Their stated mission is to minister to children, but how much should we trust that they will choose to protect the children in their care rather than the brothers and priests in their ranks who have been accused or even convicted of sexually abusing a minor?

Summary: President Trump is the third president in history voted to be impeached by the House of Representatives. Fareed Zakaria examines the history of impeachment, and what it means today.

Summary: All the best moments and all the worst moments from the year 2019.