A joint-stock company is a business entity where different stocks can be bought and owned by shareholders. Each shareholder owns company stock in proportion, evidenced by his or her shares (certificates of ownership). This allows for the unequal ownership of a business with some shareholders owning a bigger proportion of a company than others do. Shareholders are able to transfer their shares to others without any effects to the continued existence of the company.
In modern day corporate law, the existence of a joint-stock company is often synonymous with incorporation (i.e. possession of legal personality separate from shareholders) and limited liability (meaning that the shareholders are only liable for the company's debts to the value of the money they invested in the company). And as a consequence joint-stock companies are commonly known as corporations or limited companies.
Some jurisdictions still provide the possibility of registering joint-stock companies without limited liability. In the United Kingdom and other countries which have adopted their model of company law, these are known as unlimited companies. In the United States, they are known simply as "joint-stock companies".
A stock trader or equity trader or share trader is a person or company involved in trading equity securities. Stock traders may be an agent, hedger, arbitrageur, speculator, stockbroker or investor. A stock investor is an individual or company who puts money to use by the purchase of equity securities, offering potential profitable returns, as interest, income, or appreciation in value (capital gains). This buy-and-hold long term strategy is passive in nature, as opposed to speculation, which is typically active in nature. Many stock speculators will trade bonds (and possibly other financial assets) as well. Stock speculation is a risky and complex occupation because the direction of the markets are generally unpredictable and lack transparency, also financial regulators are sometimes unable to adequately detect, prevent and remediate irregularities committed by malicious listed companies or other financial market participants. In addition, the financial markets are usually subjected to speculation.