Wikipedia:HotCat

You must be logged in to use HotCat.

To turn HotCat on or off, first make sure you are logged in. Then, click on "Preferences" in the upper-right hand corner, go to the "Gadgets" tab (or use ), and scroll down to the "Editing" section. HotCat is in the middle of the list. A checked box will enable it, or uncheck the box to disable it. Scroll down to the bottom of the page and click Save. You will get a green "Your preferences have been saved" message. You can now navigate back to the page you started from; you may need to reload the page you were viewing or bypass your cache.

Whenever a page is loaded, HotCat looks for the category bar. If there are visible categories, it adds links to easily remove, change or add categories. This appears at the very bottom of the page:

The new links are:

To remove a category, simply click the "(−)" link next to the category name. If the page does indeed contain this category, HotCat will remove it automatically. It will

To change a category, click the "(±)" link next to the category name. This will open the input box where you can enter a new category name.

To add a category, click the "(+)" link at the end of the category line. This will open the input box where you can enter a new category name.

The input box of HotCat is very simple: a text field to enter the new category name, an indicator icon, and an "OK" and a "Cancel" button.

The indicator icon tells you whether or not the category name you've entered exists. A icon means that there is no such category yet. You can still add the category, but it will show up as a red link, and you should, after having added the category, click that red link and enter a brief description and parent categories to this new category. A icon shows that there already is a category with the name you've entered.

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Wikipedia