Generic software is software that can perform many different tasks and is not limited to one particular application. For example, a spreadsheet application is generic because it is useful for multiple purposes without modification, such as a calculating tool for engineers or a finance tool for accountants.
Generic software is readily available to the public. Developers design bespoke software, also known as custom software, on the other hand, for specific applications. Developers create this kind of software to suit one particular client's needs instead of the general public. Unlike generic software, it is not usually widely available for sale on the public market.