What was the dot-com bubble and what can we learn from the biggest technology crash in history?

I would like to understand what the dot-com bubble was, how it happened, and what it tells us about technology, investment, and human behaviour. What caused so much money to pour into internet companies during the late 1990s and what made investors believe that any company with a website could be worth billions? Which famous companies collapsed during the crash and which ones survived and why? What was the role of venture capital, Wall Street, and media hype in inflating the bubble? When did the crash happen, how severe was it, and how long did it take for the technology sector to recover? What happened to the people who worked at companies that failed overnight? I have also read that during this period billions of dollars were spent laying fibre optic cables under oceans to connect continents including Asia and India to the rest of the world. Companies like Global Crossing, Worldcom, and FLAG Telecom raced to build this broadband infrastructure on the assumption that internet traffic would keep doubling indefinitely. When the crash came most of these companies went bankrupt almost overnight. What happened to all that infrastructure they built and how did it shape the internet connectivity we have today, including India's technology boom in the 2000s? How did the dot-com crash shape the technology giants we know today such as Google, Amazon, and Apple? And are there parallels between the dot-com bubble and the current wave of excitement around artificial intelligence that we should be paying attention to?