What types of log files are present in Linux?

In Linux systems, there are several common types of log files.

1. System Logs: These record the overall operation and error messages of the system and are typically stored in the /var/log directory, such as /var/log/messages and /var/log/syslog.
2. User logs: These records contain information about user activities, login details, etc. They are usually stored in the /var/log directory, such as /var/log/wtmp, /var/log/lastlog, etc.
3. Application Logs: these logs record the running status, error messages, etc. of various applications, typically stored in specific directories for each application, such as Apache’s log files located in /var/log/apache2/access.log and error.log.
4. Security Logs: These logs record security events of the system, such as logins, permission changes, etc. They are usually stored in the /var/log directory, with examples being /var/log/auth.log and /var/log/secure.
5. Kernel logs: these logs record information about the running of the Linux kernel, including errors, and are typically saved in the /var/log directory, such as /var/log/kern.log.
6. Package Manager Logs are files that record the operations performed by package managing systems such as apt and yum. These logs are typically located in the /var/log directory, examples include /var/log/dpkg.log and /var/log/yum.log.

The above are common types of Linux system log files, with some additional types possibly found in different Linux distributions.