Can't find the_content()

Hello, I’m new in WP, I’m reading Customizing the read more and it mentions the_content() method. It can be replaced with the_excerpt(), but the problem is, that I can’t find where the_content() method call actually happens.

I guess summaries of the posts are in the main(index) page, I looked at template’s index.php but there is no the_content(), I tried few other templates, including default ones, but the same problem. Is the_content() method is no longer used or am I blind?

Thanks for help!