What a difference a year makes. Amazon (AMZN -1.61%) saw its stock drop 50% in 2022 thanks to rapidly rising interest rates and heightened fears about a recession crushing asset prices. This year, however, the top tech company handsomely rewarded investors. 

As of this writing, shares of Amazon are trading hands at about $140. This makes the tech giant a no-brainer FAANG stock to buy right now for less than $150. Here's why that's the case. 

Multiple growth engines 

Amazon's current market cap of $1.44 trillion and trailing 12-month sales total of $538 billion easily make this one of the largest corporations in the world. Naturally, investors would think that there isn't much growth potential left as we look over the next five to 10 years. And this could dissuade some from taking a closer look at the stock, as the prospective returns might be limited. 

That way of thinking is understandable, but I don't believe it applies to Amazon right now. This company still has lots of expansionary opportunities. Understanding its revenue drivers will provide more clarity. 

Of course, everyone knows Amazon to be the undisputed leader of online shopping, as it has 38% share of all e-commerce activity in the U.S., according to Statista. The business basically spearheaded the secular trend of online shopping, and now sells millions of items on its popular website. 

Data from the St. Louis Federal Reserve shows that even after its rise over the past couple decades, online shopping only makes up 15.4% of all retail spending in this country. That means there is still a ton of room for Amazon to grow its presence when it comes to e-commerce. 

The company also owns and operates the world's leading cloud infrastructure and services provider, Amazon Web Services (AWS). Revenue in this segment increased 12% in the latest quarter, a notable slowdown from previous years, but still sizable. AWS is extremely profitable, with an operating margin that typically exceeds 20%. And it should see tremendous growth, as the industry is estimated to be worth $1.6 trillion by the year 2030, compared to $600 billion this year. 

Investors might be unfamiliar with Amazon's success in digital advertising, a burgeoning business line that increased sales 22% to $10.7 billion in the most recent quarter. By running a website that had 3.2 billion visitors in the month of August, Amazon has one of the most popular internet properties out there. All this attention creates the perfect environment to sell digital ads, a market that will only get bigger over time. 

Bolstering the Amazon machine is the successful Prime membership offering, which has over 200 million subscribers worldwide. By offering free delivery, Prime attracts customers who crave the convenience that Amazon can provide. Additionally, Prime's video service, a top choice among viewers, benefits from the growth of streaming entertainment. 

As you can clearly see, Amazon is riding the wave of major technological trends. So even though it's already a gargantuan enterprise, it's easy to see where the gains can come from as we look toward the next decade. 

What about the valuation? 

We've established that Amazon has lots of growth opportunities that can add to its already dominant position. But investors need to be mindful of the valuation they are being asked to pay. Despite the stock's 66% rise in 2023, shares trade at a reasonable price-to-sales (P/S) ratio of 2.7 right now. That's considerably cheaper than its trailing five-year average, indicating that there's a deal for investors to take advantage of in the stock market. 

This is without a doubt one of the best businesses in the world. I don't think investors should think twice about adding it to their portfolios and holding for the long haul.