A company is a legal entity created by law that allows a group of people to come together to achieve common goals and share risks. It has a separate legal identity from its owners and can exist indefinitely over time. Some key characteristics of companies include limited liability for owners, transferable shares, and a common seal. There are several types of companies including private companies which are subject to restrictions on shareholding and transfers, public companies which can raise capital from the public, government companies which are majority owned by the government, foreign companies operating in India, and holding companies which have controlling ownership of other subsidiary companies.