The U.S. used to send a lot of its plastic waste to China to get recycled. But last year, China put the kibosh on imports of the world's waste. The policy, called National Sword, freaked out people in the U.S. — a huge market for plastic waste had just dried up.

Where was it all going to go now?

Two former Major League Baseball stars, pitcher Octavio Dotel and infielder Luis Castillo, have been implicated in a massive drug trafficking bust in the Dominican Republic. The country's attorney general, Jean Alain Rodríguez, announced Tuesday that the operation targeted alleged drug kingpin César Emilio Peralta, also known as "César the abuser," and the extensive criminal operation he led.

Italian Premier Giuseppe Conte has announced that his resignation amid political chaos and jockeying for power within his own coalition.

In a scathing speech to the Senate, Conte railed against his right-wing coalition partner, Deputy Premier Matteo Salvini. Conte is an independent. His coalition includes the anti-establishment Five Star Movement and Salvini's party, the League, which is staunchly anti-migrant and euroskeptic. Conte's government has held power for some 14 months.

If you wanted to measure your heart rate or step count during exercise, you would use a fitness tracker. But what if you wanted a device to tell you when when you need to drink more water or should reach for a sports drink?

Work at the site of France's damaged Notre Dame Cathedral resumed on Monday, after a three-week pause over concerns about lead that spewed from the fire in April.

As the blaze ripped through the 850-year-old cathedral's roof and steeple, smoke billowed out — its yellow hue a sign of burning lead — spreading toxic dust that settled on streets, homes, businesses and schools in parts of central Paris.

Two Manhattan landlords took an unusual — and illegal — route to double their rentable space: cutting their two condos in half horizontally so they could rent out 18 tiny apartments in their Lower East Side building, according to the New York City Department of Buildings.

"The ceiling heights were 4.5 feet to 6 feet tall on each level, depending on where you were standing," Department of Buildings spokesperson Abigail Kunitz said in an email to NPR.

For months, Hong Kong's streets have seethed with discontent. Scenes from the semiautonomous region show protesters, sometimes numbering in the hundreds of thousands, many wearing surgical masks and carrying umbrellas that have come to signify resistance.

The images are astonishing, and the issues that set the protests in motion are complex.

So here's a primer breaking down the major players, why they have poured into the streets and the response so far from China.