If you've learned little in your life about the stock market -- which is likely, as financial matters are not always taught in school -- you may be assuming that you need to be at least somewhat wealthy in order to invest in the stock market. That's not the case, though.

Many major brokerages these days are charging $0 per trade, and you can buy as little as a single share at a time. So if you've got, say, $1,500 accumulated in your bank account, and you have at least five or so years in which you're able to leave it to grow, you can definitely invest it in stocks.

Here are three solid candidates to consider for your portfolio.

1. Veeva Systems

Veeva Systems (VEEV -0.50%), with a recent market value topping $27 billion, specializes in cloud-based software that helps companies in various industries -- most notably the life sciences -- operate more efficiently. For example, it helps the pharmaceutical industry manage clinical trials and get them to market faster, when possible.

The company reported solid fourth-quarter results in early March, featuring fourth-quarter and full-year revenue up 16%. Notably, it gained 174 customers in the life sciences industry, ending the year with 1,388. It also doubled the number of top 20 pharmaceutical companies using its Veeva Vault EDC for new clinical trials -- from three to six. And here's one more tidbit that will impress some investors: Veeva is a Public Benefit Corporation, so "Veeva is committed to balancing the interests of all stakeholders, including customers, employees, shareholders and the industries it serves."

With its shares recently down 24% from their 52-week high, Veeva Systems sports an appealing valuation. Its forward-looking price-to-earnings (P/E) ratio, recently 40, is well below its five-year average of 67, and long-term investors would do well to take a closer look at Veeva.

2. Booking Holdings

Booking Holdings (BKNG 0.13%) has become a travel giant in the online world, serving travelers in just about every country on earth, with brands such as Booking.com, Priceline, Agoda, Rentalcars.com, KAYAK, and OpenTable. (It has subsidiary brands, too, such as Rocketmiles, Fareharbor, HotelsCombined, Cheapflights and Momondo.)

The company's performance is impressive: In 2022, 900 million room nights were booked through it, with gross travel bookings topping $120 billion. Booking's fourth-quarter report featured quarterly revenue up 36% year-over-year and net income doubling. Total bookings in 2022 grew 58% over 2021, and CEO Glenn Fogel noted, "We are encouraged by the continued strength and resiliency of demand from travelers last year and into the new year, which we believe speaks to our consumers' strong desire to use our platforms when booking their travel."

Booking Holdings' stock looks attractive at recent levels, with its forward-looking P/E ratio recently 20, well below the five-year average of 31, and the price-to-sales ratio of 6 well below the five-year average of nearly 8.

3. Pfizer

If you weren't familiar with Pfizer (PFE 1.54%) before the pandemic started, you're certainly familiar with it now. The company reaped plenty of profits from its COVID-19 vaccine, and the fact that fewer people are getting vaccinated these days has some worried about its future. Its stock was recently down 28% from its 52-week high, reflecting such worries.

Worries may be overblown, though, and the falling share price has pushed up the stock's dividend yield -- to a recent hefty 4%.

Pfizer has a rich pipeline of 110 products in development, and it's buying cancer-fighting specialist Seagen, which has its own pipeline, for some $43 billion. Meanwhile, in addition to its COVID-19 vaccine, Pfizer also sells the COVID-19 treatment, Paxlovid.

The company's fourth-quarter report featured earnings per share up 48% over year-earlier levels and full-year revenue topping $100 billion, with 10 medicines or vaccines each generating more than $1 billion each. Pfizer's recent P/E ratio of 7 is well below its five-year average of more than 15, and its price-to-sales ratio of 2.3 is well below its five-year average of 4.1.

Give these companies some consideration -- and if you're not ready to jump into any individual stocks right now, consider plunking your $1,500 into a simple, low-fee index fund, which requires little attention and is likely to serve you very well over many years.