The U.S. job market is constantly changing but now the change is more dynamic and disruptive, says Aaron Hurst, author of "The Purpose Economy."

It's no longer a question of getting a job and staying in it for a long time. "People are changing every couple of years and freelance work is becoming an incredibly large part of the job market," he said. Citing a report from financial software company Intuit, Hurst says freelancers will account for about 40% of the workforce by the end of this decade.

Related: How 'microjobs' help you ditch your boss

At the core of this change, says Hurst, is the millennial generation, born in 1980. Its members don't want to be tied to one employer, one job. They're willing to work for less money so long as their jobs have meaning and their lives purpose.

Hurst says they will "force the change" because in 10 years millennials will account for about 75% of the workforce."They're starting to become managers, directors, vice presidents and CEOs so as that happens they are starting to build the organizations they want to work in."

Related: Unhappy? Quit your job now!

Hurst says some companies are already doing a good job appealing to millennials, such as Google (GOOG), Facebook (FB), and Whole Foods (WFM).  And online shoe retailer Zappos, now owned by Amazon (AMZN), has taken a more radical approach. Months ago it eliminated job titles and more recently it stopped listing job openings. Instead, it started a new careers site through which job seekers can network with Zappos employees and build relationships.

Follow The Daily Ticker on Facebook and Twitter (@dailyticker).

More from The Daily Ticker

Could this powder replace food forever?

GM's recall report shows how lemons are built

After Apple stock splits 7-to-1, one of these 6 stocks could be next