Simply called "console", the system, also the computer console, represents the tool by which we give the computer commands in a text format and receive the results from their execution again as a text.
Generally the system console represents a text terminal, which means that it accpets and visualizes just text without any graphical elements like buttons, menus, etc. It usually looks like a black coloured window like this one:
In most operating systems, the console is available as a standalone application on which we write console commands. It is called a Command Prompt in Windows, and in Linux and Mac a Terminal. The console runs console applications. They read text from the command line and print text on the console. In this book we are going to learn programming mostly through creating console applications.