Debian is a Unix-like computer operating system that is composed entirely of free software, and packaged by a group of individuals participating in the Debian Project. The Debian Project was first announced on August 16, 1993 by Ian Murdock. Debian 0.01 was released on September 15, 1993, and the first stable release was made in 1996. The Debian stable release branch is the most popular Debian edition for personal computers and network servers, and has been used as a base for many other distributions.
Manjaro Linux, or simply Manjaro, is an open source operating system for computers. It is a distribution of Linux based on independently developed Arch Linux distribution. Within the Linux community, Arch itself is renowned for being an exceptionally fast, powerful, and lightweight distribution that provides access to the very latest cutting edge - and bleeding edge - software. However, Arch is also aimed at more experienced or technically-minded users. As such, it is generally considered to be beyond the reach of those who lack the technical expertise (or persistence) required to use it.
ls command is used to list directory contents under Linux and Unix like operating systems. It lists all files and folders in a directory at the command line, but by default ls returns a list in alphabetical order. With a simple command flag/option, you can have ls sort by file size instead, showing the largest items at the top of the ls command results. This trick applies to the ls command output in Mac OS / Mac OS X, Linux, BSD, as well as Bash in Windows.
Most Linux servers offer an SSH login via port 22 for remote administration purposes. While connecting to your server through SSH can be very secure, the SSH daemon itself is a service that must be exposed to the Internet to function properly. This comes with some inherent risk and offers a vector of attack for would-be assailants.