When it comes to stocks, there's no arguing that our market is a forward-looking machine. But all too often, investors fail to look past relatively short time frames, focusing the bulk of their attention on what might happen in the coming quarters, weeks, months, or even days. 

The largest fortunes, however, will be made by those who invest with much longer-term periods in mind. To that end, we asked three top Motley Fool investors to each discuss a stock to buy for the next generation. Read on to learn why they chose Facebook (META 2.71%), Activision Blizzard (ATVI), and Mazor Robotics (MZOR)

Baby holding coins, with money stacked in the background

IMAGE SOURCE: GETTY IMAGES

Two billion users (and counting)

Steve Symington (Facebook): When I'm considering stocks to buy for the next generation of investors and consumers alike, few companies are as well suited to the task as Facebook. The social-media titan not only has a long runway for growth for its namesake platform, but it also enjoys massive opportunities to capitalize on its smaller Instagram, WhatsApp, and Messenger applications.

During its most recent quarterly report, Facebook confirmed that it served 2.01 billion monthly active users, and 1.32 billion daily active users in June alone. Both figures marked solid 17% year-over-year growth. And though its brands remain free to use (and "always will be," it says), the company is effectively monetizing that base; advertising revenue last quarter skyrocketed 47% year over year to $9.164 billion, 87% of which came from mobile sources. On the bottom line, net income rose an even better 71% to just under $3.9 billion, and earnings per share jumped 69% to $1.32.

And for investors wondering just how long Facebook can continue growing, note that roughly two-thirds of the world's population still doesn't have access to the Internet -- something Facebook is aiming to solve through its global Internet.org initiative.

To be fair, shares of Facebook are already up nearly 50% so far in 2017 on the heels of its strong results. But with the stock trading at around 26 times this year's expected earnings -- a fair premium to pay given its outsize earnings growth -- I think this is still a compelling stock for the next generation.

Game on!

Danny Vena (Activision Blizzard): As one the top video-game publishers, Activision is already riding that trend to new heights, with its stock up 49% year to date. But it has an even greater opportunity for the next generation -- esports.

Activision announced in July that it had sold the first seven teams for its upcoming Overwatch League to a number of big names from both traditional sports and esports, including Robert Kraft of the New England Patriots and Stan Kroenke of the Los Angeles Rams, for an estimated at $20 million each. Recent reports indicate the company has completed additional deals, signing 13 of the 14 teams that will compete in the first season. This is the first global professional esports league with city-based teams.

Activision also boasts five of the top 10 most watched esports titles on Twitch, a video game live-streaming site. These include Hearthstone (No. 3), Overwatch (No. 5), StarCraft II (No. 6), Heroes of the Storm (No. 7), and Call of Duty: Infinite Warfare (No. 10) in July, according to market intelligence firm Newzoo.

Esports can generate revenue in many of the same ways as traditional sports, including media rights, advertising, sponsorship, ticket sales, and game publisher fees. Activision recently entered into a media rights partnership for some of its games.

The esports and streaming market is expected to generate $1.8 billion in 2017, and $3.5 billion by 2021, according to Juniper Research.

Activision has already raised its guidance twice this year. In its most recent quarter, Activision grew revenue by 4% year over year to $1.6 billion, while earnings per share jumped 60%. 

How to benefit from the rise of robots

Cory Renauer (Mazor Robotics): I don't think this generation or the next will need to concern itself with autonomous robots in the operating theater, but hospitals can't seem to switch from handheld scalpels to robot-assisted surgical tools fast enough. Mazor Robotics has carved out a niche for itself as the leading manufacturer of systems that allow surgeons to perform relatively routine spinal procedures with tiny instruments.

The minimally invasive procedures that Mazor's surgical systems perform lead to fewer complications and shorter recovery times. Demand from U.S. hospitals that face penalties for post-surgery readmissions has helped Mazor's second-quarter revenue explode 87% higher than the same period last year to $15.5 million.

Mazor's success has attracted competitors, but the 900-pound gorilla in the space, Medtronic, is more of an ally than a threat. Last year the pair signed an agreement that pushed up orders for new systems to record levels and involves an equity stake that aligns the device giant's interests with Mazor's.

The market for robot-assisted spinal procedures could jump from about $26 million last year to more than $2.77 billion by 2022. Right now, Mazor is the best way to ride this trend. With a tiny little market cap of just $1.1 billion at recent prices, this high flying stock has a lot of room to run in the years to come.