From the beginning, it was considered as an April Fool's joke, but now it has become one of the most important products under Google. Gmail, which went online on April 1, 2004, is celebrating its 5th anniversary. With the arrival of its 5th birthday, although the word "beta" still exists, there is no denying that Gmail has become a powerful, stable, and mature email product. Now, the Gmail logo in the upper left corner has lit up birthday candles when you log in. The "M"-shaped birthday cake with a "5" on it that Google gave to Gmail also conveys to users "Gmail is 5 years old!"