The most usual type of company, and the type that is most generally suitable for business purposes, is a company limited by shares.
In such cases, the liability of the shareholders for the debts of the company is limited to the amount they have agreed to pay for the shares they purchase in the company, but which they have not yet paid. If the company needs to, it can call on its members to pay some, or all, of the unpaid share price. Beyond that, however, the members are not required to contribute towards paying the debts of the company.
This is the most common form of company for business purposes.