Bill Gates shares the critical lesson he learned from his 4th grade teacher

When Bill Gates met Mrs. Caffiere, he was a shy 4th grader with "atrocious handwriting" and "a comically messy desk."

He also loved to read, which was "cool for girls but not for boys," the billionaire co-founder of Microsoft writes on his blog. "Mrs. Caffiere took me under her wing and helped make it okay for me to be a messy, nerdy boy who was reading lots of books."

Caffiere was the school librarian and an avid reader. She gave nine-year-old Gates a handful of books she had enjoyed and took the time to discuss them with him. "She pulled me out of my shell by sharing her love of books," Gates writes.

"I learned from Mrs. Caffiere that my teachers had so much more knowledge to share. I just needed to ask. Up through high school and beyond, I would often ask my teachers about the books they liked, read those books when I had some free time, and offer my thoughts."

Now, he asks others billionaires for their book recommendations, like Warren Buffett, who first introduced him to "Business Adventures."

"More than two decades after Warren lent it to me — and more than four decades after it was first published — 'Business Adventures' remains the best business book I've ever read," Gates writes.

Gates, who goes through about 50 books a year, carves out time to read no matter how hectic his day may be. After all, reading is a core habit of the most successful people — and science shows that it could benefit you in more ways than one.

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