STEP, as STandard for Exchange of Product model data, is aimed to support a complete and unambiguous description of industrial products all along their life cycle, independently of any computer system (operating system, hardware, CAD software ..).
This standard is used in data exchange between softwares used in the industry (CAD, Analysis, PDM, etc..), which takes a greater and greater place in the industry, so it is more and more a requisite for software providing. It is a strategic matter in the domain of CAD data exchanges, to support this standard, giving the applications the means to communicate with others in a collaborative engineering process.
Designing, producing, maintaining… a product generates and uses various kinds of information from the beginning to the end of its lifecycle. These informations are created and used by various systems, softwares, etc.. at different times, which can moreover be located in several sites.
To satisfy such constraints involves to keep completeness and consistency of product data when exchanging them in such open frame : a common computer sensible form is then needed to represent them.
So, to summarize, STEP provides a neutral way of describing informations relevant for a product, all the steps of its life cycle, relying on a set of general formalisms. Its general purpose is to allow communication between various systems in a company or between companies, in a context of concurrent engineering, reaching key criteria : independence from hardware platforms, from operating systems…, interoperability between softwares, longevity of archived data, extensibility, in order to get current technical innovations, without having to translate former data just for "coding" issue, modularity to allow exchange of the various data kinds involved during the life cycle of products. In addition, STEP clearly separates data descriptions and their physical exchange (like file formats, etc).
STEP is known and managed as an ISO standard, we can say a family of standards, because it covers numerous domains : it is organized in a series of parts, each of them is published separately (ISO series 10303, managed by ISO technical committee TC184/SC4Some of these parts are known as Application protocols (APs) to describe product data for an application or a consistent set of applications. STEP uses a formal specification language, EXPRESS, for specifications : this enables precision and consistency of representations and makes implementations easier.
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