[This is part of the series: The Complete Guide To Economics 101.]
In the world of economics, what is capital?
Capital is usually referred to as durable goods, used in the production process, of a given good or service.
To that, I would also include, non-durable goods and financial assets used to facilitate the production process.
But at this point, we are splitting hairs. And others would probably disagree.
It is one of the three classical factors of production.