Baidu knows how many categories there are in a ***?

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Category: /browse/

There are currently 14 first-level classifications.

Each field under the first-level classification has a second-level classification, some second-level classifications have a third-level classification, and some third-level classifications (such as regions) have a fourth-level classification, which is more intuitive. You can view the category list:

/misc/alltop?type=all