UK companies are businesses registered in the United Kingdom. They can take various forms, including limited companies, partnerships, and sole traders. Each type has different legal structures and responsibilities, affecting how they operate and are taxed. Companies must adhere to regulations set by Companies House, which oversees their registration and compliance. In the UK, companies contribute significantly to the economy, providing jobs and services across various sectors. They are required to file annual accounts and reports, ensuring transparency and accountability. The Companies Act 2006 governs company law, outlining the rights and duties of directors and shareholders.