Starbucks (SBUX -2.43%) has become so successful that it defines the idea of a coffee house in the United States.

Gone are the days of local stores with ratty furniture, hipster employees, and poetry slams on a makeshift stage. That has been replaced with a comfortable sameness. Starbucks stores have familiar menus, friendly, well-trained baristas, and even clean bathrooms.

Before Starbucks, many Americans did not know the difference between a latte and a cappuccino and we certainly weren't ordering the half-caf, light foam, extra shots, and soy milk. Starbucks has literally created new sizing terms which we all accept -- Tall, Grande, and Venti are made-up terms. But, the company still has some secrets and a few things you may not know.

1. There are two secret sizes on the menu. Though they are rarely officially referenced by the company it's possible to order a "Short," an 8-ounce cup, and the more widely known "Trenta," a 31-ounce size mostly used for iced teas. It is possible to order pretty much any cold drink as a Trenta, though not every store will honor this.

Trenta is the big one Source: Starbucks

Trenta is an official size for iced coffee and tea -- though it does not appear on menu boards -- but you can also order Frappuccino in the massive size.   

2. Starbucks owns a host of brands. Some of which, like Teavana and Evolution Fresh, get featured in its stores. In other cases however, specifically with Seattle's Best Coffee, and Tazo Tea, the company does not make an effort to make the corporate lineage clear. In some ways that lets the company be its own competition as someone who opts for Seattle's Best or Tazo as an anti-Starbucks choice, may be surprised when they learn the truth.

3. During its fourth-quarter earnings call in October CEO Howard Schultz said that 21% of all its in-store transactions were made via mobile payment and he seems encouraged by its growth potential.

"Although we only completed the rollout of Mobile Order & Pay across our system -- 7500 U.S. company-owned store portfolio -- in September, we were already operating at a run rate of over five million transactions per month," he said. "And that figure, believe it or not, is growing by the hour."

4. The chain originally did not serve drinks. Before Starbucks had become a national brand or really any semblance of the company it is now, it was a coffee roaster in the Seattle area. In his autobiograph, CEO Howard Schultz detailed his struggle to get the then management to serve completed beverages (like European cafes) along with the beans.

5. In 2010 Stabucks become the first brand to reach 10 million likes on Facebook. It happened just after Lady Gaga became the first person to achieve the feat, AdWeek reported. Currently the company's page has over 36 million likes, which places it consistently in the top five brands on the social media platform.

6. Starbucks closed 2015 with 23,043 stores across the globe.  It's coffee rival Dunkin' Donuts has "more than 11,300 Dunkin' Donuts restaurants worldwide," according to the company -- 8,000 in 41 states in the U.S. plus the District of Columbia, and more than 3,200 international restaurants in 36 countries. Starbucks has had locations in all 50 states since 2000, but it only has seven in Vermont, seven in Alaska, and eight in Hawaii, according to its store locations map.

7. When Howard Schultz came back to take over as CEO in 2008 due to the company's falling fortunes he was pressured by certain investors to cut employee healthcare costs by dropping coverage for part-time employees. Schultz refused and in 2010 the company spent more on healthcare than it did on coffee beans. The company still provides health insurance to any employee who works at least 20 hours a week and the benefit has helped the company recruit and retain employees.

8. Until 2015, the Pumpkin Spice Latte, one of the chain's most popular seasonal drinks did not contain any real pumpkin. 

The Pumpkin Spice Latte Source: Starbucks

"After hearing from customers and partners about ingredients, we took another look at this beverage and why we created it so many years ago," said Peter Dukes, director of Espresso and Brewed Coffee in a press release. "It was simple – espresso, perfectly steamed milk, warm fall spices with delicious flavor of pumpkin pie that reminds you of the cool, crisp days of autumn. It's the Pumpkin Spice Latte our customers have loved all along."

9. Starbucks has always been an employee-friendly company. In 1991 it became the first privately owned company that extended its stock option program to part-time employees, wrote my Fool colleague Tamara Walsh.

10. Since June of 2014 the coffee chain has offered employees a free online college education through Arizona State University. Any U.S. employee who works an average of 20 hours a week at any company-owned store is eligible for the benefit, which is offered immediately upon hire.

11. In 2014 during the holiday season one in seven Americans received a Starbucks gift card, representing a total value of $1.6 billion, COO Kevin Johnson said during the Q4, 2015 earnings call. Throughout the entire fiscal 2015, he noted, card loads (the amount of money added to cards) was $5.1 billion, a 19% increase over the previous year.