The verb know is converted into the noun Knowledge (জ্ঞান) in its most standard abstract form.

১. Known is the past participle or adjective form, while knowledgeable is an adjective.
২. Knowing can be a gerund (noun-like verb), but ‘knowledge’ is the primary noun entity.
৩. Adding suffixes like ‘-ledge’ often transforms verbs into abstract nouns in English.

অতিরিক্ত তথ্য: The plural form of knowledge is not commonly used as it is an uncountable noun.