What is checked and unchecked exception ?

Answer 1

checked exception are compile time errors, that means compiler check the exceptions in compilation time. Unchecked exception are run time errors, these are not checked by the compiler, these exceptions are only noticed at runtime.

Answer 2

https://www.geeksforgeeks.org/checked-vs-unchecked-exceptions-in-java/

Answer 3

https://www.sololearn.com/learn/Java/2177/?ref=app