Start here
A Plain Guide to Digital Files, Folders and Formats
How computers turn documents, photos and music into stored data, what folders really are, and why so many different file formats exist.
Devices and Tools
Files, Storage and Formats
What files are, how they are stored and how formats differ.
How Cloud Sync Differs From Backup
A synced folder mirrors changes, including deletions and damage, while a true backup keeps older copies. Learn the difference and why it matters.
How Deleted Files Really Work
What happens when you delete a file: recycle bins, freed space, why data may linger on a drive, and why secure erasure is a different step.
How File Compression and Zip Files Work
Learn how compression shrinks files, the difference between lossless and lossy methods, and what a zip archive does when you bundle files together.
Image Formats Explained: JPEG, PNG and WebP
Compare JPEG, PNG and WebP by file size, quality and transparency, and learn which picture format usually suits photos, screenshots and web graphics.
Organizing Files So You Can Find Them Later
Practical naming and folder ideas for personal documents, including dates, consistent names and shallow structures that keep files easy to search.
PDF Files Explained and Why They Behave Oddly
Why a PDF keeps its layout on every device, how it differs from an editable document, and why changing text, copying content or reading scans can be awkward.
USB Drives, Memory Cards and Other Portable Storage
How flash-based USB sticks, SD cards and portable drives store data, what speed ratings mean, and why data on unplugged storage is not kept forever.
What File Extensions Tell You
What the letters at the end of a file name mean, how your computer uses them, why renaming does not convert a file, and how hidden extensions can mislead.
Related topics
More in devices and tools
Computer Care Basics Choosing, tuning and protecting the computer you own. Cloud Tools for Small Teams What cloud storage, backup and work apps offer and where they fall short. Smart Home Voices Speakers and assistants in the home, and the trade-offs of living with them. Phones and Tablets Understanding the phone or tablet in your pocket and how to look after it. Home Wi-Fi and Networking How home internet connections work and why they sometimes struggle.