The stock (also capital stock) of a corporation constitutes the equity stake of its owners. It represents the residual assets of the company that would be due to stockholders after discharge of all senior claims such as secured and unsecured debt. Stockholders' equity cannot be withdrawn from the company in a way that is intended to be detrimental to the company's creditors.
During the Roman Republic, the state contracted (leased) out many of its services to private companies. These government contractors were called publicani, or societas publicanorum as individual company. These companies were similar to modern corporations, or joint-stock companies more specifically, in a couple of aspects. They issued shares called partes (for large cooperatives) and particulae which were small shares that acted like today's over-the-counter shares. Polybius mentions that “almost every citizen” participated in the government leases. There is also an evidence that the price of stocks fluctuated. The Roman orator Cicero speaks of partes illo tempore carissimae, which means “shares that had a very high price at that time." This implies a fluctuation of price and stock market behavior in Rome.
A stock derivative is any financial instrument which has a value that is dependent on the price of the underlying stock. Futures and options are the main types of derivatives on stocks. The underlying security may be a stock index or an individual firm's stock, e.g. single-stock futures.
Stock futures are contracts where the buyer is long, takes on the obligation to buy on the contract maturity date, and the seller is short, takes on the obligation to sell. Stock index futures are generally delivered by cash settlement.
A stock option is a class of option. Specifically, a call option is the right (not obligation) to buy stock in the future at a fixed price and a put option is the right (not obligation) to sell stock in the future at a fixed price. Thus, the value of a stock option changes in reaction to the underlying stock of which it is a derivative. The most popular method of valuing stock options is the Black Scholes model Apart from call options granted to employees, most stock options are transferable.
They may also simply wish to reduce their holding, freeing up capital for their own private use. They can achieve these goals by selling shares in the company to the general public, through a sale on a stock exchange. This process is called an initial public offering, or IPO.
By selling shares they can sell part or all of the company to many part-owners. The purchase of one share entitles the owner of that share to literally share in the ownership of the company, a fraction of the decision-making power, and potentially a fraction of the profits, which the company may issue as dividends. The owner may also inherit debt and even litigation.
In the common case of a publicly traded corporation, where there may be thousands of shareholders, it is impractical to have all of them making the daily decisions required to run a company. Thus, the shareholders will use their shares as votes in the election of members of the board of directors of the company.
In a typical case, each share constitutes one vote. Corporations may, however, issue different classes of shares, which may have different voting rights. Owning the majority of the shares allows other shareholders to be out-voted – effective control rests with the majority shareholder (or shareholders acting in concert). In this way the original owners of the company often still have control of the company.
Alternatively, debt financing (for example issuing bonds) can be done to avoid giving up shares of ownership of the company.
Unofficial financing known as trade financing usually provides the major part of a company's working capital (day-to-day operational needs).