As the needs of each client.

Systems for enterprise resource planning (English ERP, Enterprise Resource Planning) are information management systems that integrate and automate many business practices associated with operating or productive aspects of a company.

ERP systems are integrated management systems for the company. They are characterized by being composed of different parts into a single integrated application. These parts are of varying use, eg production, sales, purchasing, logistics, accounting (various types), project management, GIS (geographic information system), inventory and warehouse control, ordering, payroll, etc.. We can define an ERP as the integration of all these parties. The opposite would like to consider a simple billing program as an ERP for the simple fact that a company integrates only that part. This is the fundamental difference between an ERP and other management application. The ERP integrates everything needed for the operation of the business processes of the company. ERP can not talk about at the time that only integrates one or a small part of business processes. The very definition of ERP indicates the need for "all information available to everybody all the time."
The main objectives of ERP systems are:

Optimization of business processes.
   

•       Access to all information in a reliable, accurate and timely (completeness of data).
  
•       The possibility of sharing information between all components of the organization.
  
•       Elimination of unnecessary data and operations reengineering.
  

The fundamental purpose of an ERP is to provide support to business customers, faster response times to problems and an efficient management information enabling timely decision making and reduced total operating costs.
The distinguishing features of any other ERP enterprise software, is that they must be comprehensive, with modular and adaptable:

      Comprehensive, because different processes can control the company's understanding that all departments of an enterprise are interrelated, ie the result of a process is the starting point of the next. For example, in a company, a customer placing an order is to create a sales order triggers the production process, inventory control, planning, product distribution, collection, and of course their ledger entries . If the company uses an ERP, you need to have several programs that control all these processes, with the disadvantage of not being integrated, information is duplicated, increasing the scope of pollution in the information (especially for entry errors) and creates a favorable scenario for embezzlement. With ERP, the operator simply capture the order and the system takes care of everything else, so that the information is handled and protected.

      Modular. The company understand that ERP is a set of departments that are interrelated with the information they share and that is generated from their processes. One advantage of the ERP, both economic and technical is that the functionality is divided into modules which can be installed in accordance with customer requirements. Example: sales, materials, finance, warehouse control, human resources, etc..

      Adaptable. The ERP are created to suit the idiosyncrasies of each company. This is accomplished through the configuration or parameterization of processes in accordance with outputs that are needed for each. For example, for tracking inventory, a company may need to handle the partition of lots but no other company. The most advanced ERP programming tools typically incorporate 4th Generation for rapid development of new processes. The parameterization is the fundamental value that should have any ERP to suit the specific needs of each company.

Other features of ERP systems are:

• Central database.
  
• ERP components interact with each other to consolidate all operations.
  
• In an ERP system data is entered only once and must be consistent, complete and common.
  
• Companies that implement it are having to change any of its processes to align with the ERP system. This process is known as Business Process Reengineering, although not always necessary
  
• Although the PRA may be configurable modular menus according to the roles of each user, is a whole. This means: it is a single program (with multiple libraries, of course) with access to a centralized database. Not to be confused at this point the definition of an ERP with a management suite.
  
• The current trend is to offer specialized applications for specific companies. It is what is called sectoral or sectoral applications versions particularly suited or prepared for certain business processes in a sector (most used).