Home Depot is a major chain of big-box (large square area) stores that sell tools, lumber, appliances, paint and other items related to building, carpentry and home improvement. If you have ever been to a Wal-Mart, it is a lot like that except that the theme is orange in color and everything in the store has to do with fixing or renovating homes or buildings. Home Depot investors are people who have purchased shares of stock in the company. They own a portion of that company depending on the number of shares of stock that they bought.