The activities undertaken by banks; this includes personal banking (non-business customers). commercial banking (small and medium-sized busi ness customers). and corporate banking (large international and multinational corporations). In the USA there are many restrictions on banks opening branches across the nation, notably the Glass Steagal Act (1933). Consequently, unit banking is mainly undertaken through separate enterprises, although the restrictions have been breached on several occasions and there are now many super-regional banks in the USA, operat ing in a similar way to UK _branches. In the UK most banking for both business and personal customers is undertaken through the High-Street banks, which is also known as branch banking (see also COMMERCIAL BANK).