John the Ripper is a well-known password cracking tool used to test the strength of passwords by performing brute-force, dictionary, and hybrid attacks. It is commonly used by security professionals during penetration testing and password audits to identify weak credentials.
Burp Suite is a web application testing tool, Nslookup is a DNS query utility, and Wireshark is a packet analyzer. None of these tools are designed specifically for password cracking.
While John the Ripper can be used maliciously, it is also widely used defensively to improve password policies and enforce strong authentication practices. Its existence highlights the importance of strong passwords, hashing, salting, and multi-factor authentication.