Warren Buffett and Bill Gates, the first- and third-richest people in the world, are good friends. Image source: Flickr user Ethan Bloch.

This article was originally published on May 20, 2015, and was updated on April 5, 2016.

It's good to have goals. If you're aiming to be one of the top 10 richest people in the world, you might want to start by learning whom you have to knock off the list, how wealthy they are, and how they built their massive fortunes.

Forbes magazine is a big help here, as it regularly lists  the richest people in the world. The magazine goes beyond the top 10, too, keeping tabs on all billionaires (their total: 1,810). Let's see what Forbes' data shows us.

The top 10 richest people in the world
First off, here are Forbes's "The Richest People on the Planet 2016":

Rank

Name

Net Worth

Source of Wealth

1

Bill Gates

$75 billion

Microsoft

2

Amancio Ortega

$67 billion

Zara

3

Warren Buffett

$61 billion

Berkshire Hathaway

4

Carlos Slim Helu

$50 billion

telecom

5

Jeff Bezos

$45 billion

Amazon.com

6

Mark Zuckerberg

$45 billion

Facebook

7

Larry Ellison

$44 billion

Oracle

8

Michael Bloomberg

$40 billion

Bloomberg LP

9

Charles Koch

$40 billion

Koch Industries

9

David Koch

$40 billion

Koch Industries

Source: Forbes

Here are some other interesting things  about these folks and their fellow billionaires:

  • Anyone thinking that the U.S. has the vast majority of the world's richest people will find gobs of non-Americans on the list. Spain's Amancio Ortega, for example, is ranked No. 2, while Mexico's Carlos Slim Helu is in fourth place, with Liliane Bettencourt of France in 11th place. Forbes' list of billionaires features 570 from the United States but also includes 251 from mainland China, 69 from Hong Kong, and 77 from Russia, among many other nations.

Many Americans haven't heard of Mexico's Carlos Slim Helu, but he's the world's fourth-richest man. Photo: ITU Pictures, Flickr

  • There are a record number of billionaires under age 40 on the big Forbes list, at 66. That's still a tiny minority, however, reflecting the fact that it's not easy to become a billionaire quickly. Some noteworthy names on the list include 31-year-old Mark Zuckerberg, founder of Facebook., 39-year-old Travis Kalanick of Uber, and 32-year-old Elizabeth Holmes of Theranos, a medical testing company.

  • As you might expect, not all of the billionaires are self-made. Many, such as Walton family members, inherited their wealth from the Wal-Mart business. Others, such as famous right-wing activists Charles and David Koch, inherited great wealth and then increased that wealth significantly. Most on the overall list are self-made.

  • Many of these billionaires have joined the Giving Pledge campaign  created by Bill Gates, Melinda Gates, and Warren Buffett, promising to donate at least half of their fortune. Some of the pledgers include Netflix founder Reed Hastings, Dan Gilbert of Quicken Loans, Virgin founder Richard Branson, co-founder of America Online Steve Case, and Spanx founder Sara Blakely.

It's unlikely that any of us will become one of the top 10 richest people in the world, but that doesn't mean we need to give up our dreams of financial security. By saving aggressively and investing effectively (perhaps via a simple, inexpensive broad-market index fund) for a long time, many of us can at least become millionaires. That will take us most or all of the way to a comfortable retirement.