When we talk about a "successful" person, we're typically talking about someone who's got billions in their bank account, someone who's authored multiple bestsellers, or maybe someone who's in charge of an entire nation.
But if you ask people who fit the conventional definition of a successful individual, many will tell you that those achievements aren't what make them feel accomplished.
Below, Business Insider has rounded up what some of the world's most powerful and impressive people — from President Barack Obama to the late author Maya Angelou — have to say about success.
Billionaire Richard Branson believes success is about happiness.
Though Sir Richard Branson, founder of the Virgin Group, is worth some $5 billion, the Virgin founder equates success with personal fulfillment.
"Too many people measure how successful they are by how much money they make or the people that they associate with," he wrote on LinkedIn. "In my opinion, true success should be measured by how happy you are."
Huffington Post co-founder Arianna Huffington says that money and power aren't enough.
Huffington says that while we tend to think of success along two metrics — money and power — we need to add a third.
"To live the lives we truly want and deserve, and not just the lives we settle for, we need a Third Metric," she told Forbes' Dan Schawbel, "a third measure of success that goes beyond the two metrics of money and power, and consists of four pillars: well-being, wisdom, wonder, and giving."
Together, those factors help you to take care of your psychological life and truly be successful, or as the title of her 2014 book, "Thrive," suggests.
Billionaire investor Mark Cuban says you don't need money to be successful.
"Shark Tank" regular Cuban offers a surprisingly simple take on success.
In an interview with Steiner Sports, he said:
"To me, the definition of success is waking up in the morning with a smile on your face, knowing it's going to be a great day. I was happy and felt like I was successful when I was poor, living six guys in a three-bedroom apartment, sleeping on the floor."
Legendary basketball coach John Wooden said it's a matter of satisfaction.
With 620 victories and 10 national titles, Wooden is the winningest coach in college basketball history.
But his definition of success was more about competing with yourself than the other guy:
"Peace of mind attained only through self-satisfaction in knowing you made the effort to do the best of which you're capable," he said in a 2001 TED Talk.
Legendary investor Warren Buffett values relationships above all else.
As James Altucher writes, the chairman of Berkshire Hathaway once told shareholders at an annual meeting: "I measure success by how many people love me."
Acclaimed author Maya Angelou believed success is about enjoying your work.
The late, great poet laureate, who passed away at 86 in 2014, left behind stacks of books and oodles of aphorisms.
Her take on success is among the best: "Success is liking yourself, liking what you do, and liking how you do it."
Microsoft cofounder Bill Gates believes it's about making an impact on society.
Gates is the wealthiest person in the world, with a net worth of $86 billion, But to him, success is about relationships and leaving behind a legacy.
"Warren Buffett has always said the measure [of success] is whether the people close to you are happy and love you."
He added: "It is also nice to feel like you made a difference — inventing something or raising kids or helping people in need."
Spiritual teacher Deepak Chopra believes success is a matter of constant growth.
The physician and author says it's a matter of continual growth.
"Success in life could be defined as the continued expansion of happiness and the progressive realization of worthy goals," Chopra writes in "The Seven Spiritual Laws of Success."
President Barack Obama aims to change people's lives.
Obama once held the highest office in the land — but he doesn't equate power with success.
At the 2012 Democratic National Convention, First Lady Michelle Obama told the audiencethat her husband "started his career by turning down high-paying jobs and instead working in struggling neighborhoods where a steel plant had shut down."
She went on:
"For Barack, success isn't about how much money you make. It's about the difference you make in people's lives."
Inventor Thomas Edison recognized that success is a grind.
So naturally, his definition of success is equally ambitious: "Success is 1% inspiration, 99% perspiration."
Popular author Stephen Covey said that the definition of success is deeply individual.
The late Covey became a massive success — and a part of popular culture — with his 1989 book, "The Seven Habits of Highly Effective People," which has sold over 25 million copies.
Yet for Covey, success was categorically individual.
"If you carefully consider what you want to be said of you in the funeral experience," he writes in the book, "you will find your definition of success."
Billionaire John Paul DeJoria sees success as working hard — all the time.
DeJoria co-founded Paul Mitchell hair products and Patron tequila. In an interview with Business Insider, he reflected on the lessons he learned while working at a dry cleaner's as a young man.
Apparently, the head of the store was impressed by how spic and span DeJoria kept the floors, even though no one was watching him clean.
That's why he now believes:
"Success isn't how much money you have. Success is not what your position is. Success is how well you do what you do when nobody else is looking."