What is an operating system ?
In order to run all those components, you need to have a software, this software is named an operating system. An operating system, is, as its name stands for it,
the software which is in charge of running your full system, so to say
According to the kind of device you will use, the operating system (OS) may be totally different. For example on desktop computers the market is composed of Microsoft Windows and MAC solutions, the mobile market is mostly Android and ios, the server market is mostly GNU/Linux.
Most of operating systems are providing you a GUI, a Graphical User Interface, it makes it easy to perform from there the different interactions. Though, don't be surprised, if you deal with developers, you will often see that they are not having fun with the GUI but with the CLI, the Command Line Interface, where you can directly write to the computer in order to perform specific actions.
Within the FLOSS Marketing School, we are mostly using the GNU/Linux operating system, so we will mainly refer to it. In this part of the course we will assume that you already have an operating system running on your computer. So we will skip the part about installing it, even if it will be probably the subject of another course.
Once you are connected you will land on a screen named the desktop. On the desktop you may find many shortcuts to program or files, but also what we call the launcher. As its name stands for it, the launcher is the place from where you can start all the applications that you have within your computer.
In general, developers won't use the desktop and will access straight away to the shell by using the following shortcut ctrl+alt+t.
In fact, a device, when purchased, should be delivered without any operating system (unless the manufacturer is also the one of the OS, for example with Mac), but as it is highly technical, in general computer manufacturer are passing contracts with OS companies, so as Microsoft.
Ok, so you have now your operating system up and running, first action you will be asked is to connect to a session. A session is a space which will be personal, so only you will be able to access it, unless you give your credentials to someone else. Note also that if your hard disk is not encrypted, it is always possible to access your data by adding another operating system on your computer.
Note as well that in GNU/Linux you have the host session, it allows you to let your computer to someone else and everything performed within this session will be lost at the next connection.
At the top bar of the desktop you will see some icons such as the wifi logo, the synchronization of app and extra features.
- Lock the computer: it allows you to put on hold your computer. It is highly advised to add a password here. The idea is the following one, if someone access your machine they cannot access to your data.