I want to transfer my videos and pictures from my iPhone to my PC.

Indeed, but that copies a selection of content from your computer to your device. The content in the camera roll may get backed up during sync sessions, but it doesn't become available to use on your computer elsewhere unless you take explicit steps to transfer it. That can be with a suitable app (would not recommend Apple Devices as that will break iTunes) or by manually copying files from the device's DCIM folder into the computer using Windows Explorer. Earlier versions of that article provided this information, but I see it is missing now. Sigh.

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The other article guides you to Use iTunes to sync your iPhone, iPad, or iPod with your computer - Apple Support that says:

"What you can sync with iTunes

• Albums, songs, playlists, movies, TV shows, podcasts, and audiobooks.
• Photos and videos.
• Contacts and calendars."

Follow the instructions in:

Sync your iPhone, iPad, or iPod using your computer - Apple Support

See Transfer photos and videos from your iPhone or iPad to your Mac or PC - Apple Support. The other article relates to copying media from your computer to the device.

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