What is inorganic?
Inorganic compounds are simple compounds which contain carbon. Salts of inorganic cations including carbonates, cyanides, cyanates, thiocyanates and carbides, carbon monoxide, carbon dioxide are some examples for inorganic compounds.
The organic vs inorganic fertilizer could be a small bit of a misnomer since as you compost things, they inevitably get broken down into fundamental building blocks which are the same as what you’d provide with mineral or chemical fertilizers.
As an example, urine is rich in phosphorus, potassium and nitrogen ‘organic fertilizer’, but composts so rapidly and has such a tall concentration of completely broken down natural compounds that it isn’t appallingly diverse from a fluid fertilizer and it’s a nice replacement instead of synthetic nitrogen fertilizer.