How to check your disk’s health in Linux using smartmontools?

The smartmontools package contains two utility programs (smartctl and smartd) to control and monitor storage systems using the Self-Monitoring, Analysis and Reporting Technology System (SMART) built into most modern ATA/SATA, SCSI/SAS and NVMe disks. In many cases, these utilities will provide advanced warning of disk degradation and failure.

— Official description from smartmontools.org