Each time I reinstall windows 10, what does it create

When you reinstall Windows 10, the following actions typically occur:

**System Files**: Windows 10 creates a new set of system files, including the core operating system files required for running the OS.

**Windows Registry**: A new registry is created, which is a database that stores settings and options for the operating system and applications.

**User Profile**: If you set up user accounts during the installation, Windows creates user profiles. Each user profile includes folders like Desktop, Documents, Downloads, Pictures, etc.

**Drivers**: Windows installs default drivers for hardware devices (like graphics cards, network adapters, etc.). You may need to install specific drivers later for optimal performance.

**Program Files**: The `C:\Program Files` and `C:\Program Files (x86)` directories are created, which are default locations for installed applications.

**System Recovery Options**: Windows creates recovery partitions to help recover the system in case of issues.

**Temporary Files**: During installation, Windows may create temporary files and folders that are used during the process.

**Paging File**: A paging file (also known as a swap file) may be created to assist with memory management.

**System Updates**: After installation, Windows will typically check for updates and may download and install them.

**Default Settings**: Windows creates default settings and configurations, which may include privacy settings, accessibility options, and personalization settings.

If the installation is done from a clean slate (formatting the drive), previous data on the drive may be erased unless backed up beforehand. Also, if you chose an upgrade option, your files and applications can remain intact (though this is not a complete reinstall in the traditional sense).