Linux (pronounced or, less frequently) is a Unix-like computer operating system assembled under the model of free and open-source software development and distribution.

The defining component of Linux is the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds.

The Free Software Foundation uses the name GNU/Linux to describe the operating system, which has led to some controversy.

HTTPS (also called HTTP over TLS, HTTP over SSL, and HTTP Secure) is a protocol for secure communication over a computer network which is widely used on the Internet.

HTTPS consists of communication over Hypertext Transfer Protocol (HTTP) within a connection encrypted by Transport Layer Security, or its predecessor, Secure Sockets Layer.

The main motivation for HTTPS is authentication of the visited website and protection of the privacy and integrity of the exchanged data.

Android is a mobile operating system developed by Google, based on the Linux kernel and designed primarily for touchscreen mobile devices such as smartphones and tablets.

Android's user interface is mainly based on direct manipulation, using touch gestures that loosely correspond to real-world actions, such as swiping, tapping and pinching, to manipulate on-screen objects, along with a virtual keyboard for text input.

In addition to touchscreen devices, Google has further developed Android TV for televisions, Android Auto for cars, and Android Wear for wrist watches, each with a specialized user interface.

Variants of Android are also used on notebooks, game consoles, digital cameras, and other electronics.

A virtual private network (VPN) is a virtualized extension of a private network across a public network, such as the Internet.

It enables users to send and receive data across shared or public networks as if their computing devices were directly connected to the private network.

Applications running across the VPN may therefore benefit from the functionality, security, and management of the private network.

The File Transfer Protocol (FTP) is a standard network protocol used for the transfer of computer files from a server to a client using the Client–server model on a computer network.