compareTo() in java

Question

I have read in a book that "compareTo( ) is specified by the Comparable<T> interface, which String implements".
What does it means?

Answer 1

https://www.sololearn.com/discuss/869592/?ref=app
https://www.sololearn.com/discuss/1158758/?ref=app
https://www.sololearn.com/discuss/890780/?ref=app
https://www.leepoint.net/data/expressions/22compareobjects.html

https://docs.oracle.com/javase/7/docs/api/java/lang/Comparable.html
https://www.tutorialspoint.com/java/java_string_compareto.htm
https://www.javatpoint.com/java-string-compareto
https://beginnersbook.com/2013/12/java-string-compareto-method-example/

https://www.javatpoint.com/java-string-equals
https://www.javaworld.com/article/2072762/java-app-dev/object-equality.html