Fastest-Growing all-stars

The company first made the list in 2003, taking the No. 66 spot. It has made the list every year since, settling in at no. 83 in 2012. Though Cognizant is based in the U.S., most of its operations and workforce are in India, where in 2011 it overtook Wipro Ltd. as the country's third largest software exporter by sales. In 2012, it surpassed India's IT bellwether Infosys for the second top spot.

Looking ahead, its uncertain how Cognizant will fair as Europe's debt crisis could potentially get worse. The company has warned the region would remain a drag on sales. In May, Cognizant lowered its full-year forecast for the first time in nearly four years.

Apple

With the naming of a new CEO mid-year 2011, all eyes have been on Apple. The Cupertino, CA-based multinational debuted on this list at no. 6 in 2007, and has continued to hold a place above no. 40 each year. For 2012, landed the no. 8 spot.

Apple has gained from its blockbuster products. Demand for iPads and iPhones has spawned a market for downloadable apps that let users handle various tasks from shopping to playing games. And in turn, apps have fed consumers' demand for Apple's products. The company had $127.8 billion in sales during the 2011 calendar year, putting it neck-and-neck with Hewlett-Packard, the nation's largest tech company.

Competitor Samsung has quickly caught up, but the tide could turn just as quickly for the South Korean smartphone maker. In September 2012, a California jury ruled Samsung infringed Apple mobile phone patents. This puts pressure on Samsung to overhaul how it makes handsets, as the company faces the prospects of a ban on eight phones in the U.S. and hefty fines.

Intuitive Surgical

The Sunnyvale, CA-based manufacturer of robotic surgical systems continued to gain with growing demand for robotic surgery. Its da Vinci technology is used heavily in medical procedures such as hysterectomies, and has helped the company hold steady on this list since 2007 when it came in at no. 4. Intuitive slipped to no. 50 in 2012, but the company has seen business grow. For 2011, revenues grew 24% over the previous year, while profit rose 30% and surgical procedures using the da Vinci system rose 29% to 360,000 during the same period.

For 2012, Intuitive Surgical gave a cautious note on spending by hospitals in Europe, where governments are grappling with too much debt. The company gets 20% of its annual revenue from Europe and foreign markets like Japan and South Korea.

AsiaInfo-Linkage

After merging with rival Linkage, this IT firm and software provider has been expanding its business globally, reaching everywhere from Southeast Asia to Europe.

Asian Info-Linkage has been on the list for four years in a row, starting at no. 40 in 2009 and settling at no. 84 in 2012. It has had big successes catering to China's telecommunications industry. And more recently, it has deepened its footprint in Southeast Asia's burgeoning telecommunications markets by signing an agreement with Malaysian telecommunications provider U Mobile to offer postpaid and prepaid mobile services as well as other communications services.

Despite worries over Europe's debt crisis, the company in 2012 opened its European headquarters as part of its effort to expand globally.

HMS Holdings

Being in the business of detecting waste in the dizzying world of healthcare has paid off for HMS Holdings. The company mines health claims and government and private data and spots inefficiencies, fraud and abuse.

In 2009, HMS made its debut on this list at no. 20 and has held steady each year since. It fell to no. 92 in 2012 but is still seeing healthy gains. For 2011, revenues rose 20.1% to $363.8 million over the previous year.

HMS has also deepened its expertise, with the acquisition of HDI Holdings, which provides improper payment identification services for government and commercial health plans.

Celgene

Coming off a few major acquisitions, the Summit, NJ-based biopharmaceutical company continued to gain in 2011. Celgene first made it onto this list in 2009, coming in at No. 22. Since then, it has continued to be among the Fortune's fastest growing companies every year as the company works to become an oncology leader.

Celgene continued winning with the successes of popular drugs Revlimid and Vidaza for blood and bone marrow conditions. For 2011, revenues rose by 34% to approximately $4.8 billion over the previous year.

The company has seen some setbacks, however. It has been trying to win approval in Europe to widen use of blood cancer drug Revlimid, but withdrew its application recently in a move that stunned investors. The drug is already approved in Europe and the U.S. to treat multiple myeloma, but Celgene has been seeking to offer the treatment sooner to myeloma patients and as a maintenance therapy.

Chipotle Mexican Grill

An appetite for sustainably made tacos and burritos has kept this popular Mexican fast-casual chain on Fortune's Fastest-Growing Companies list.

For 2011, revenues rose by 23.6% to $2.27 billion. The Denver, CO-based chain was also the best-performing restaurant stock in the Standard & Poor's 500 Index. Chipotle has more than 1,100 restaurants, mostly in the U.S. The chain also has locations in London and Toronto, and in May 2012 opened a store in Paris.

And while it has made its mark in customized Mexican delights, the chain has opened its first Asian-themed restaurant, ShopHouse Southeast Asian Kitchen, in Washington, D.C. What's next? Indian?

Ebix

This Atlanta-based technology company has been on Fortune's list for the past four years. It supplies on-demand software and e-commerce services to the insurance industry, and has largely grown through a string of key acquisitions.

In June 2012, Ebix announced it would buy PlanetSoft, a life insurance technology firm. This followed acquisitions last year of Australian information technology firm Fintechnix, as well as Montreal-based Taimma, which provides e-learning medical education solutions to the pharmaceutical, biotechnology and healthcare industries.

For fiscal year 2011, revenues grew by 28% to $169 million over the previous year. But not everyone believes the company's growth is entirely legit. In a 2011 lawsuit, Ebix was accused of inflating earnings from its 2009 fourth quarter -- a charge that the company has repeatedly denounced.

Green Mountain Coffee Roasters

For the past four years, Green Mountain has held steady on the Fastest-Growing list. It has expanded substantially, having dominated the U.S. single-cup coffee market with its K-cups -- a staple in corporate offices.

But Green Mountain faces significant headwinds. For one, it stands to lose patent protection for K-Cups this year, which could crimp revenues and profits going forward. And its stock plummeted last September amid questions over the company's growth and accounting methods.

Nonetheless, the company has show investors it has a promising future. In March, Green Mountain announced what could potentially be a lucrative partnership with Starbucks. It would sell Starbucks-branded single serving packs to run with Green Mountain's newest coffee machine, the Vue.

Catamaran Corp.

Formerly SXC Health Solutions, Catamaran handles drug benefits for corporate clients and health plans. The company changed its name in July 2012 after SXC acquired rival Catalyst Health Solutions Inc., creating the nation's fourth-largest pharmacy benefit manager behind Express Scripts Holdings Co., CVS Caremark Corp. and a division of UnitedHealth Group Inc.

SXC has been on Fortune's Fastest Growing Companies list for the past three years. It debuted at no. 6 in 2010 and topped 2011's list. It has slipped to no. 11 in 2012, but is still growing strong.

With its acquisition of Catalyst, the company is poised for further growth, as the deal is expected to drive the company's annual revenues to $13 billion.

Coinstar

Benefitting largely from its Redbox movie-rental kiosks, the Bellevue, WA-based DVD specialist has held steady onto Fortune's list for the past three years. It ranked no. 61 in 2010 and has steadily risen to no. 15 in 2012.

The company has gained from hard times at Netflix, where hundreds of thousands of U.S. subscribers dropped the service after the company in July 2011 raised prices for both streaming and DVDs to $15.99 from $9.99. But just as Coinstar was gaining from such defections, the company raised the price of a nightly rental cost for standard DVDs to $1.20 from $1.

Despite higher costs, the company is aiming to grow. It plans to expand its kiosk business and develop a joint venture to offer video streaming with Verizon Communications Inc. And it also plans to enter the coffee business, having announced a joint venture with Starbucks to sell Seattle's Best Coffee in U.S. vending machines.

F5 Networks

The Seattle-based computer networking company has seen business boom, thanks largely to strong demand for its Viprion application and security products. Founded in 1996, F5 helps companies efficiently and securely manage data traffic across complex computer networks.

The company has been on Fortune's list for the past three years, debuting at no. 64 in 2010 and staying steady as no. 53 in 2012.

For fiscal year 2011, revenue rose by 31% to $1.15 billion over the previous year.

Medifast

The business of delivering low-fat meals to people's doors has kept Medifast on the list for the past three years. It first appears on the list at no. 29 in 2009, then rose to no. 5 in 2010 and slipped to 46 in 2011.

Medifast's business model has helped it grow over the years. Not only does the company sell healthy meals and snacks, but it also develops personal diets and counsels clients.

For fiscal year 2011, revenue increased by 16% to $298.2 million over the previous year. However, competitors are gaining steam. Medifast missed sales and earnings estimates twice in 2011. And rival Weight Watchers International, known for its "points" system for scoring your meals, has been quickly gaining in the $60 billion weight-loss industry.

Priceline

Despite worries over Europe's ongoing debt crisis, the biggest U.S. online travel agency by stock market value continued to grow. The company saw robust sales in 2011, which made up more than half of its total revenue.

It has been on Fortune's list for the past three years, starting off at no. 11 in 2009 and staying steady at no. 14 in 2011.

Priceline's Booking.com, a European business purchased in 2005, has been helping the company take sales from rivals Expedia Inc. and Orbitz Worldwide Inc.