You can tag your files, assets for easier management. Unlike folder where 1 asset can only belong to 1 folder, 1 asset can have many tags.
You can use tags to easier filter for certain type of assets.
To tag your asset, just select your assets in the Files/Assets view by clicking the circle on top right of each assets.
Then click the Edit Tag button on the button bar.
Type in your tag name or if you already have tags, you can select from the existing list.
At any point of time, you can filter for assets with certain tag by clicking on the Tag in the right panel