Marketo, founded by Philip Fernandez, sells software that companies can use to consolidate their online, social, and mobile marketing activities into one platform. To stand out from other software marketing companies, Marketo touts its customer-service tools, which include consulting services and discussion forums for Marketo customers. The company says its goal is to help customers navigate the evolving digital market landscape. Marketo faces stiff competition, however, from large, enterprise-level software companies that are now getting into the marketing software game, including Oracle and SAP. To stay innovative (and to continue meeting the changing needs of its customers), Marketo says it plans to release a new application for its marketing platform every 12 to 18 months for the foreseeable future. Note: employee count as of Dec. 31, 2015

Spun out of Stanford University, business analytics company Tableau Software was founded by Christian Chabot, Chris Stolte, and Pat Hanrahan. The three co-founders also played a hand in the invention of a data-visualization language called VizQL, implemented in Tableau's original software. The company aims to help businesses see and understand their data better, selling software that turns data points into visual presentations. Tableau's history of profitability has been spotty--it turned a profit in 2013 and 2014, and then lost money in 2015--so it is unclear how successful the company will be in the future. But Tableau feels that it is well positioned, since the business-analytics-software industry is still relatively new. Note: employee count as of Dec. 31, 2015

Aerohive Networks, founded by Changming Liu, wants to make it easier for large companies and organizations to install Wi-Fi. The company created a Wi-Fi network that can be managed through the cloud, reducing the need for physical controllers, which take up space and can be costly. Currently, the majority of Aerohive's customers are businesses in the health care and education sectors. But to turn around its history of losing money, Aerohive needs to attract customers that represent a broader variety of markets. To do so, the company plans to increase its sales team. Note: employee count as of Dec. 31, 2015

It's easy to miss given all the trouble plaguing Jack Dorsey's other company, Twitter, but Square has had a remarkably good run of late. When Dorsey launched Square eight years ago with co-founder Jim McKelvey, the San Francisco company focused on selling credit card payment systems to small businesses. But now, Square's ever-popular gadget is just one of its many products. "Today, sellers come to Square for much more than payments and hardware," Dorsey told investors earlier this year.

Square is becoming, in other words, a one-stop shop for small businesses: You can get invoices and payroll services there, or even speedy cash through its lending program, Square Capital, which has extended $1.3 billion since its 2014 launch. And Square has even gotten into the on-demand food-delivery business by buying Caviar. New products launched since 2014 now account for a full quarter of the company's adjusted revenue. As John T. Williams, an analyst at Compass Point Research & Trading, puts it, "A lot of the business lines they've added tie in very nicely with Square's original product." --Victoria Finkle

Houston banking company Allegiance Bancshares may have burst onto the national stage with an IPO in 2015, but founders George Martinez and Steve Retzloff want the company to focus on doing business in Texas. Allegiance operates almost exclusively in the Houston metropolitan area. The company deals primarily with small and medium-size businesses and consumers. Staying local has worked out well so far, but should Houston’s economy take a hit (as it has in early 2016 from falling oil prices), the company could find itself in trouble. To grow its community footprint, Allegiance is directing its efforts toward identifying and acquiring other banks in Houston. Note: employee count as of Dec. 31, 2015