What Is an Operating System?
An operating system (OS) is the core software that manages a computer's hardware and lets you run apps, store files, and interact with the device. It sits between the hardware and every other program, handling tasks like memory, processing, storage, and security. Windows, ChromeOS, macOS, and Linux are the most common operating systems for laptops and desktops.
The operating system is the most important type of system software. It shapes how your PC looks and feels, which apps you can install, and how the device is updated and protected.
Operating system essentials at a glance
An OS manages hardware resources and provides a platform for apps
It provides the interface you use, such as the desktop, taskbar, and settings
Apps are usually built for a specific OS and don't run on others without a compatible version
Each OS has versions and editions that receive updates for a set period
Most new HP Windows PCs come with Windows 11, and HP Chromebooks run ChromeOS
What Does an Operating System Do?
An operating system coordinates everything that happens on a computer, from the moment it starts until it shuts down. After the system firmware checks the hardware at startup, it loads the OS, which then takes over these core jobs:
OS function | What it means | Everyday example |
|---|---|---|
Process management | Schedules processor time so multiple apps can run at once | Streaming music while editing a document |
Memory management | Assigns RAM to active apps and frees it when they close | Keeping several browser tabs open without crashing |
Storage and file management | Organizes files and folders on the drive | Saving, searching for, and opening a photo |
Device management | Uses drivers to control hardware and connected devices | Printing a page or connecting a wireless mouse |
User interface | Provides the screens, menus, and controls you interact with | The Start menu, taskbar, and Settings app |
Security and user accounts | Controls sign-in, permissions, and built-in protection | Signing in with a PIN or fingerprint |
Networking | Manages Wi-Fi, Ethernet, and Bluetooth connections | Joining a Wi-Fi network |
Updates | Delivers security patches and new features | Installing a monthly Windows security update |
The OS relies on drivers and firmware to talk to specific hardware. That's why keeping drivers current is just as important as updating the operating system itself.
What Are the Main Laptop and Desktop Operating Systems?
The four main operating systems for laptops and desktops are Windows, ChromeOS, macOS, and Linux. Windows runs on the widest range of PCs, ChromeOS powers Chromebooks, macOS runs only on Apple computers, and Linux is a free, open-source option available in many versions.
Windows
Windows, made by Microsoft, is the most widely used desktop operating system. It runs on laptops, desktops, all-in-ones, and workstations from many manufacturers, including most HP PCs. Windows supports the broadest range of software, games, and accessories, which makes it a flexible choice for home, school, work, gaming, and creative projects.
The current version is Windows 11, which requires specific hardware, including a compatible processor and Trusted Platform Module (TPM) 2.0. Windows 11 comes in several editions, such as Home and Pro. Shop HP Windows laptops to see current models.
ChromeOS
ChromeOS, made by Google, is a lightweight operating system built around the Chrome browser and cloud-based apps. It runs on Chromebooks, Chromebook Plus devices, and Chromeboxes. ChromeOS starts quickly, updates automatically in the background, and can also run Android apps from the Google Play Store and some Linux apps.
Because much of the work happens online, Chromebooks often need less local storage and processing power than Windows PCs. Google has announced plans to rebuild ChromeOS on an Android foundation, so features may change on future devices. Learn more about Chromebooks.
macOS
macOS is Apple's operating system for its own laptops and desktops. It's licensed to run only on Apple hardware, so you can't install it on a Windows PC or Chromebook. macOS is known for its tight integration with other Apple devices and services.
Linux
Linux is a free, open-source operating system that comes in many versions called distributions, or distros. Popular distributions include Ubuntu, Fedora, Debian, and Linux Mint. Linux is widely used by developers, on servers, and in technical and scientific fields. It can be installed on many PCs, though hardware and software support varies by distribution and device.
Other operating systems you may encounter
Mobile devices use mobile operating systems, such as Android and iOS. Businesses use server operating systems to run networks and websites. Many printers, smart TVs, and other devices run embedded operating systems designed for one specific purpose.
Windows vs. ChromeOS vs. macOS vs. Linux
The biggest differences between operating systems are which devices they run on, which apps they support, and how they're updated. This table summarizes the key distinctions.
Windows | ChromeOS | macOS | Linux | |
|---|---|---|---|---|
Developer | Microsoft | Apple | Open-source community and companies | |
Runs on | PCs from many manufacturers | Chromebooks and Chromeboxes | Apple computers only | Many PCs; support varies by distribution |
App sources | Microsoft Store, developer websites, game platforms | Web apps, Google Play Store, some Linux apps | Mac App Store, developer websites | Package managers, app stores, developer websites |
Software compatibility | Widest range of desktop apps and PC games | Web and Android apps; limited full desktop apps | Broad creative and productivity apps | Strong for development tools; fewer mainstream commercial apps |
Offline use | Full | Many apps work offline; designed around the cloud | Full | Full |
Updates | Monthly security updates and an annual feature update | Automatic background updates every few weeks | Annual major release plus security updates | Varies by distribution |
Typical users | Home, school, business, gaming, creative work | Students, schools, web-focused everyday use | Apple device users, creative work | Developers, IT professionals, technical users |
Cost | Usually included with a new PC; sold separately otherwise | Included with a Chromebook | Included with Apple computers | Usually free |
These are general characteristics. App availability, features, and update schedules vary by device, edition, and distribution.
Understanding OS Versions, Editions, and Support
An OS version is a specific release of an operating system, while an edition is a package of that version with a different set of features. For example, Windows 11 is the operating system, version 25H2 is a release of it, and Home and Pro are editions. Each version receives security updates only for a set period, so knowing which one you have helps keep your PC protected.
How Windows 11 versions work
Microsoft releases one Windows 11 feature update each year, usually in the fall. Each version is named for the year and half-year of its release, so 25H2 means 2025, second half. Monthly security updates are released in between, typically on the second Tuesday of each month.
According to Microsoft's Windows 11 lifecycle information, each version of the Home and Pro editions is supported for about 24 months. Enterprise and Education editions receive about 36 months. Installing the latest feature update when it's offered keeps your PC on a supported version.
Windows 10 reached end of support on October 14, 2025. PCs still running Windows 10 no longer receive regular security updates unless they're enrolled in Microsoft's Extended Security Updates program.
Windows 11 Home vs. Windows 11 Pro
Feature | Windows 11 Home | Windows 11 Pro |
|---|---|---|
Best for | Personal and home use | Business, advanced users, and IT-managed PCs |
Core apps, security, and updates | Included | Included |
BitLocker drive encryption | Not included (device encryption on supported hardware) | Included |
Remote Desktop host | Not included | Included |
Join a work domain or Microsoft Entra ID | Not included | Included |
Group Policy and business management tools | Not included | Included |
Hyper-V virtualization | Not included | Included |
You can upgrade from Home to Pro by purchasing an upgrade through Windows settings. Learn more about business PCs.
How ChromeOS versions work
ChromeOS updates automatically every few weeks without interrupting your work. Each Chromebook has an Auto Update Expiration (AUE) date, after which it stops receiving ChromeOS updates. Google publishes these dates, and many recent models receive updates for up to 10 years from release.
32-bit vs. 64-bit operating systems
A 64-bit operating system can use more than 4GB of RAM and run 64-bit apps, which are faster and more secure. Windows 11 is available only in 64-bit versions, and nearly all modern PCs and operating systems are 64-bit.
How to check your OS version
On Windows 11:
Select Start, then Settings.
Select System, then About.
Under Windows specifications, find your edition and version.
On a Chromebook:
Open Settings.
Select About ChromeOS.
Find your version number and update status, including the AUE date under Additional details.
Learn how to keep your laptop updated.
How to Choose an Operating System
Choose an operating system based on the apps you need, how you'll use the device, and what other devices you already own. Because the OS usually comes with the computer, choosing an OS and choosing a laptop are often the same decision.
If you need... | Consider | Why |
|---|---|---|
The widest app and accessory support | Windows | Runs most desktop software, PC games, and peripherals |
PC gaming | Windows | Most PC games and gaming platforms are built for Windows |
Simple, web-focused computing or a school device | ChromeOS | Fast startup, automatic updates, and easy management |
Business software and IT management | Windows 11 Pro | Adds encryption, remote access, and domain management tools |
Programming, servers, or open-source tools | Linux or Windows | Linux is common for development; Windows also supports Linux tools |
Specialized creative or engineering apps | Check the app's requirements | Some professional apps support only one OS |
Questions to ask before you decide
Do my must-have apps run on this OS? Check the developer's website for supported platforms and versions.
Do I work offline often? Windows runs full desktop apps offline, while Chromebooks rely more on web apps.
What accessories will I connect? Confirm that printers, drawing tablets, and other devices have drivers for the OS.
How long will updates last? Check the version's support period or the Chromebook's AUE date.
Who will manage the device? Schools and businesses may require a specific OS or edition.
For more help choosing hardware, see our laptop buying and setup guide or compare laptop types.
Frequently Asked Questions About Operating Systems
Can a computer run without an operating system?
A computer can power on without an operating system, but it can't run apps or do useful everyday tasks. Without an OS, the system firmware starts the hardware and then shows an error because no bootable OS is found.
Can I install a different operating system on my laptop?
Many Windows laptops can run Linux, either instead of Windows or alongside it. Installing a different OS may erase your data, may not support every hardware feature, and can affect manufacturer support. macOS is licensed only for Apple computers.
Is ChromeOS the same as Windows?
ChromeOS is not the same as Windows. ChromeOS is a lightweight, cloud-focused operating system for Chromebooks that runs web and Android apps. Windows is a full desktop operating system that runs traditional desktop software, including most PC games.
What happens when an operating system reaches end of support?
When an operating system reaches end of support, the developer stops releasing security updates and fixes for it. The computer still works, but it becomes more vulnerable to malware, and newer apps may stop supporting it.
Do I need to pay for Windows updates?
Windows 11 feature updates and monthly security updates are free for PCs running a genuine, licensed copy of Windows 11. Upgrading from Windows 11 Home to Windows 11 Pro requires a paid upgrade.
