How can you check disk space usage on a Linux system?

The command to check disk space usage on a Linux system is 'df -h'. This command is specifically designed to provide information about disk space usage on all mounted filesystems. The '-h' option stands for "human-readable," which means that it formats the output in a way that is easy for users to understand, using units like KB, MB, or GB rather than raw byte counts.

When you run 'df -h', you can quickly see how much space is used and available on each filesystem, along with relevant details such as the filesystem type and mount point. This makes it a straightforward and efficient way to monitor disk usage across the system.

Other options, such as 'disk -usage' and 'space -check', are not standard commands in Linux, which is why they wouldn't return useful information. Although 'du -sh' is a valid command that checks the disk usage of specific directories, it operates at the directory level rather than providing a summary of all mounted filesystems like 'df'. Thus, 'df -h' is the appropriate choice for a general overview of disk space usage.