It was in the nineties that people began worrying about computer systems becoming obsolete with new technologies not working with them. The concept of middleware gained popularity to allow the new applications to be used with old systems. However the term middleware has been in use since 1968. It is a fact that technology giants keep on developing latest software to replace older, but this means getting rid of the hardware as well. These big corporations have taken upon themselves to lessen the burden by making available open source middleware. Some of the prominent vendors of open source middleware are IBM, Oracle and Red Hat. You would surprised to know that for this very purpose many companies came into existence.
For a layman, middleware refers to programs that allow communication of sorts between two applications. This gluing of applications, using middleware is call Enterprise Application Integration (EAI). The most common use of middle ware is to access data base through a program that was intend to access another database. Wiki describes it as a piece of software that connects two or more software applications so that they can exchange data. There can be various types of middleware depending upon the requirements, and some of these are describe below.
Middleware for Messaging
This is a type of software that allows transformation and routing of messages
To interact with different databases, we use middleware that acts as an intermediary allowing access.
Transaction processing monitors and web application servers make use of this type of middleware
We know that any operating system is just software that makes possible the use of hardware. In much the same way, middleware is software that makes a distributed system programmable. If you do not have an OS, it is a very tedious process to write programs to make use of the hardware. Similarly, without using middleware, it is well nigh impossible to program a distributed system.