ls
list directory contents,
du
estimate disk usage,
nnn
terminal file manager
find
search for files and text in files, grep
curl
, wget
download file,
rsync
remote and local file-copying tool
chown
change file owner and mode, chmod
less
view the content of a text file
apt
Debian package management system,
rpm
Red Hat package manager,
yum
utility using RPM package manager
systemd
system and service manager,
journalctl
viewer of logs collected by systemd
Kernel modules, ACPIAdvanced Configuration and Power Interface (ACPI)
How to handle files that begin with special characters in their filenames - TecMint