Operating Systems — Important Questions

Microsoft Windows

Step 1: A GUI (Graphical User Interface) uses graphics, icons, menus, and buttons for interaction. Step 2: Microsoft Windows is the most popular example of a GUI-based OS where users click on icons. Step 3: MS-DOS is a Command Line Interface (CLI) based OS where users type commands. Step 4: UNIX in text mode is also a CLI-based OS, though it can have GUI shells added on top. Step 5: Other examples of GUI-based OS are Linux (with KDE/Gnome) and macOS (Macintosh).

Open-source operating system

Step 1: Linux is an open-source operating system, meaning its source code is freely available to anyone. Step 2: Developers and users can view, modify, and redistribute the source code. Step 3: It is NOT developed by Microsoft — Windows is developed by Microsoft. Step 4: Apple develops macOS (Macintosh OS) and iOS for their devices. Step 5: Linux is used on desktops, servers, and many devices, but it is not exclusively for smartphones. Android (which is based on Linux) is the smartphone OS owned by Google.

Kernel

Step 1: Linux has three main components — Kernel, System Library, and System Utility. Step 2: The Kernel is the core part of Linux and is responsible for major activities of the operating system like managing CPU, memory, and devices. Step 3: The System Library contains special functions that allow application programs to access the Kernel's features. Step 4: The System Utility is responsible for doing specialized, individual-level tasks. Step 5: Think of the Kernel as the brain of the OS — everything passes through it.

Google

Step 1: Android is an open-source mobile operating system. Step 2: It is owned and maintained by Google. Step 3: Apple owns iOS, which runs on iPhone, iPad, and iPod devices. Step 4: Microsoft owns Windows Phone OS for mobile devices. Step 5: Samsung uses Android OS on most of its smartphones but does not own Android. Because Android is open source, many manufacturers like Samsung, OnePlus, etc. use it on their devices.