categorical

بسم الله الرحمن الرحیم
با سلام
منظور از categorical در بحث سیستم تشخیص نفوذ چی هست؟
متنش هم در زیر گذاشتم:
Then, the elimination of the categorical features is done
by removing any feature with categorical data. The purpose
of this process is to use only numerical data in our distance
calculation, because for the categorical data the distance
calculations are difficult and depend on the data itself. We
could use the matching technique, but it would not help to
distinguish the records in terms of the total distance.
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