system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How do browsers make money?

How does Chrome make a profit for Google?  How does Mozilla make money?
gpt
Not all web browsers do make money. Some are open source software maintained by members of the open source community. Others, such as Internet Explorer, are commercial programmes but are offered free as an element of other paid-for software packages or operating systems, such as Windows XP or Vista. Browsers such as Firefox do make money, although they are free to the end user. They earn revenue from companies such as Google who pay a referral fee to Firefox for searches done via the built-in search bar.