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What is a computer file?

When we want a computer to remember data for later, we store it in a file.
To make it easier to sort through our files, we give each file a memorable name.
An illustration of 3 files. The first file icon has lines on it and is labeled "notes.txt". The second file icon has a butterfly picture and is labeled "butterfly.png". The third file icon has a video player icon and is labeled "film.mov".
The computer keeps track of additional details, like when the file was last updated, the type of file, and who's allowed to edit it. That's called metadata: the data about the data.
Here's a file listing from my Mac:
Screenshot of file listing, showing 4 rows of files, with columns for "Date modified", "Size", and "Kind".
Clicking on an individual file pops up a dialog with even more metadata:
Screenshot of file details for "harddrive.jpg", showing metadata like "Kind", "Size", "Where", "Created", and "Modified".
In this lesson, we'll dive deeper into two very important bits of metadata: the file kind and the file size.

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