What should I watch out for when dual-booting Linux and Windows?

If your desktop has room for two internal drives, that’s the setup I’d recommend: leave Windows on its original drive and install Linux on the second one. On a laptop, check whether a second drive can actually be installed; many models only have one storage slot. If there’s only one drive, dual-booting from separate partitions can still work, but backups become even more important. Trying Linux first on an expendable computer is a good way to practice, although booting a live session from USB is usually enough to test it safely.

You don’t have to install Linux onto a USB drive. A bootable USB is mainly used to start a temporary “live” Linux session or launch the installer. That lets you test hardware and get a feel for the desktop without changing the internal drive. Installing Linux permanently to a basic USB flash drive is usually slow and not very practical. You can also use a multiboot tool to keep several Linux installer images on one USB.

The most important step is making backups before touching partitions. Save critical files to an external drive, and ideally create a full system image so you can restore Windows if something goes wrong. You can usually shrink the Windows partition to create unallocated space, then install Linux there. On a desktop, using a separate physical drive for Linux is generally safer and easier than sharing one drive. If you do that, disconnect the Windows drive during installation so the installer can’t accidentally modify it, then reconnect it afterward and choose the Linux drive as the first boot device.

The biggest installation mistake is selecting the option that erases the entire disk instead of installing alongside Windows or into the intended free space. Read every installer screen carefully and confirm the drive and partitions before formatting anything. On newer Windows systems, firmware settings, Secure Boot, fast startup, and updates can occasionally affect the boot menu, so keep a Windows recovery drive available. Linux updates or Windows updates may sometimes change the default boot entry, but this is usually repairable through the firmware boot menu or a Linux recovery environment.