How it works: Think of bots as robotic assistants, acting in the background to simplify and streamline some of the less exciting but necessary aspects of digital work: scheduling meetings, approving expense requests, and probably somewhere, submitting TPS reports in triplicate, "Office Space"-style.

The broader industry goes by the faceless term "robotic process automation" (RPA), which perfectly describes the mundane nature of what the bots do, while obscuring just how enormous their impact might eventually be.

"When people think of automation, they think of actual robots," says Kevin Roose, a tech reporter at the New York Times and the author of the new book "Futureproof: 9 Rules for Humans in the Age of Automation." "But RPA is a huge industry that basically no one knows exists, and it really is accelerating."

By the numbers: A recent report by Gartner found spending on enterprise software is expected to grow 8.8% to $505 billion this year, with much of the money flowing to RPA and other forms of digital work automation.

The forced shift to remote work sped the trend -- in a survey by Deloitte last year, 73% of global executives reported their company was investing in intelligent automation, up from 58% in 2019.

UiPath, a global leader in RPA, announced a $750 million fundraising round last month and is currently valued at $35 billion, with plans to go public later this year.

Be smart: Not every bot can be classified as AI, but they are getting smarter. And while artificial intelligence can't yet handle the general tasks that humans can in the workplace, the machines can be very good at automating specific tasks.

The more robotic that digital workflow in the modern office becomes -- meaning broken down into discrete, repeated tasks -- the more room there is for bots to take over.

A single intelligent bot can't fully replace, say, a human HR worker, but over time, bots will likely be able to perform more and more of the tasks that make up that worker's job.