Many people find some time for shopping at this time of year, looking for Christmas gifts for loved ones -- and occasionally even a gift to themselves. No matter who you're buying for this holiday season, don't overlook stocks. Considering good stocks and the companies they represent a piece of increase in value over time, making such a purchase could ultimately be a valuable present. 

Where do you shop for good stocks? Often, they represent companies that are well-positioned to capitalize on long-term secular trends. Here are three trends in society at the moment that are unstoppable and three companies that can take financial advantage of these trends for years to come.

A smartphone displays the PayPal app in a restaurant setting.

Image source: PayPal.

1. Digital payments

The end of cash has been hastened by the COVID-19 pandemic. Consider the recently published 2020 Travis Credit Union Cash Survey. It found that people currently have health concerns about using cash and many are even avoiding situations where cash will be needed. But more than that, switching from cash to credit, debit, or fintech options has a lasting effect. The survey found that 58% of people plan to stop using cash altogether after the pandemic, and 49% want to see physical money disappear completely. 

Digital payments giant PayPal (PYPL 2.90%) already processes almost $900 billion in annual payment volume, but this is just the tip of the iceberg of what's possible. For example, global digital-commerce sales were $6.9 trillion in 2019, according to the 2020 McKinsey Global Payments Report. By 2023, this market alone is expected to generate $15.3 trillion in sales. Keep in mind that PayPal has broader application than just e-commerce sales, yet this single category provides it with plenty of upside potential.

The societal shift toward digital payments and the massive market opportunity is part of the reason PayPal stock has gone up in each calendar year since eBay spun it off into an independent company. But let's not forget that PayPal isn't passively riding higher with the tide -- it's also a great business in its own right.

PayPal continues to rapidly grow its user base of 361 million, up 22% year over year. And by successfully onboarding individuals and merchants, revenue continues to rise. Its revenue comes with an impressive trailing-12-month 25% free-cash-flow margin, leaving plenty of optionality for providing future shareholder returns.

A Roomba vacuum cleaner cleans a tile floor.

Image source: iRobot.

2. Home automation (aka the Internet of Things)

"Hey robot, get me a drink!" Colin Angle, founder and CEO of iRobot (IRBT 13.15%), hopes a robot will be able to obey that command within five years. The company currently only sells floor-cleaning robots and it's been a good, profitable business. Year-to-date this little company has generated $886 million in revenue (up 12% year over year) and earned $134 million in net income (up 105% year over year). But Angle has long-term aspirations beyond cleaning your floor.

Everything in our homes -- from thermostats, refrigerators, and iRobot's vacuum cleaners -- is getting smarter. Many of these items need to connect to the internet, playing into the Internet-of-Things trend. But more importantly, if a product offers convenience at the right price point, it's likely to be adopted long term. Accordingly, iRobot is building a direct-to-consumer customer base (almost 8 million people currently) in hopes of selling them new product lines down the road.

Our homes will continue to get smarter and more automated in time -- this is an unstoppable trend. But there's another unstoppable trend that will help iRobot: an aging population. According to the U.S. Census Bureau, the elderly population in the U.S. is expected to double over the next 20 years. As people prefer to age in their homes, these could use some robotic assistance for a variety of tasks. While the company is mum on specifics right now, it's working on product lines to address this issue, which could greatly increase its addressable market.

Many computers connect to a central image of a cloud.

Image source: Getty Images.

3. Big data

Building upon the previous two trends, data creation is growing by the day. Smart devices, digital payments, and much more result in valuable data points. And it's only increasing. According to Data Age 2025, an IDC report sponsored by Seagate Technology, there were 33 zettabytes (1 zettabyte equals 1 trillion gigabytes) of data in 2018. By 2025, it's expected this number will swell to 175 zettabytes -- an incomprehensible number. Some call this the big-data trend.

Multiple businesses are springing up around the proliferation of data, including analytics, transfer, and artificial intelligence. But data also needs a place to live. Increasingly, data lives in the cloud, and Amazon.com (AMZN 3.43%) has one of the top cloud businesses in the world. So far in 2020, Amazon Web Services (AWS) has only provided 12.5% of the company's sales but 70.6% of the operating profit, demonstrating its worth to this mega-cap company.

Despite AWS's rapid 30% year-over-year revenue growth through the first three quarters of 2020, there's still a long runway for future growth. In a recent AWS blog post, the company noted that 70% of Fortune 500 companies still haven't migrated fully to the cloud. This is likely even more prevalent among smaller operations. To help less tech-savvy businesses make the move, AWS is approving official partners that can help oversee the process. Expect this move to reduce friction and help it to continue taking market share in this ballooning industry.

Years of trending growth opportunity

Digital payments, home automation, and big data are three unstoppable trends, providing years of opportunity for the best-positioned businesses. I believe PayPal, iRobot, and Amazon are three such businesses, which in the long term should reward shareholders who jump in this Christmas season.