The phrase Investment Bank refers to a business that helps other businesses (and also governments) borrow money from other people and businesses and/or allow businesses to partially or fully sell themselves to other people and businesses. Unlike a regular bank, they do not typically lend their own money or use their own money to purchase part or all of a business, but instead they help to match the business financing need to those other business and personal investors who are seeking to earn money by either lending to the business or owning part of the business.