Marijuana is going mainstream. That's not news. What is news is how many times the subject of marijuana percolated to the top of Facebook's trending topics last week. A story has to be pretty big to become a trending topic.

It's not like on Twitter where trending topics are often hashtags related to Twitter's real time signal. It's one of Twitter's best features. Twitter moves at the speed of the internet so much so that when Michael Jackson died in 2009, his passing was a trending topic on Twitter two hours before any major news site "broke" the news.

Five years ago, it would’ve been unimaginable to think that marijuana – legal marijuana, in particular – would be one of the hottest and fastest-growing industries in the United States. And yet, with only a handful of states having implemented legalization laws, here we are. Marijuana sales are blowing up, thousands of jobs are being created, and it seems almost inevitable that prohibition is going to fall nationwide in the near future.

He became a stoner cultural icon in 1978 with “Up in Smoke,” the first of a lucrative series of Cheech & Chong movies that comically celebrated pleasures of pot during a wholly illicit era for marijuana.

Tommy Chong went on to go to federal prison in 2003 after pleading guilty to distributing drug paraphernalia by selling bongs and water pipes over the Internet. At 65, he announced he’d quit smoking the marijuana herb that made him famous and rich.

Years later, he was stricken with cancer, underwent tumor removal surgery and became a born-again medical marijuana user and advocate.

The businesses are legally unable to write checks or make credit card transactions, raising questions of safety as people carry huge sums

The Sacramento branch of the California tax collection agency reeks of marijuana.

That’s because it’s cash day at the collection center – when marijuana dispensary owners are allowed to bring in paper money to pay their quarterly sales tax bill – and the smell of their inventory clings to everything.

A new legal cannabis shop in the US state of Colorado is receiving potshots for its proximity to a strip club and ties with the mayor. 

The Smokin' Gun Apothecary opened in the space previously occupied by the popular strip club Shotgun Willie’s, which is now across the parking lot.

Both businesses are owned by the wife of the mayor, who apparently thinks there's a crossover audience.

Deborah Dunafon wants to offer tokers discounted drinks at the strip club by selling mugs.

She also thinks the stoners will bring a chiller vibe to her not-so-gentlemanly club.

The first thing you notice when you walk into the Bud & Breakfast called "B and B 420" is that it's really, really clean. It's that feeling of relief you get when you realize that the place you're staying will be nice — better than nice, nicer than your house. The second thing you notice is the faint smell of fresh marijuana in the air, your one gram sample waiting for you in a tupperware on the coffee table tray, beside some rolling papers and a pipe.

As Washington, Colorado and Oregon report "record-setting" legal marijuana sales in 2015, it doesn't come too much as a surprise that the weed industry is proving and growing to be much bigger in the next few years.

In fact, according to cannabis research firm ArcView Market Research, in conjunction with New Frontier data, legal marijuana sales are projected to hit $21.8 billion in total annual sales by 2020. That's four times the size of legal weed sales in 2015.

Notably, there are moderate advantages to be garnered from medicinal cannabis. Unfortunately, it also possess some disadvantages which should be considered. Marijuana can reverse cognitive decline…as long as it’s not laced with toxic pesticides. One of the most surprising and recent revelations about cannabinoids are their capability to perform as antioxidants in the brain. German experts have found that the brain’s cannabinoid system has the capability of restoring impaired brain cells, while developing new ones. Cannabinoids may curb the effects of Alzheimer’s, Parkinson’s, Huntington’s disease and possibly more.

GW Pharmaceuticals hopes that its big-time spending on medical marijuana research could finally prove worthwhile.

Marijuana drug developer GW Pharmaceuticals plc (NASDAQ:GWPH) is plowing tens of millions of dollars into marijuana research and development every quarter, but trial failures in cancer pain and schizophrenia last year are increasing worry that its efforts will prove futile.

This year, GW Pharmaceuticals expects to report data from a slate of trials evaluating its marijuana drug Epidiolex in epilepsy patients. Can these trials get the company back on track? Read on to find out what's at stake.