In standardization, a profile is a subset internal to a specification. Aspects of a complex technical specification may necessarily have more than one interpretation, and there are probably many optional features. These aspects constitute a profile of the standard. Two implementations engineered from the same description may not interoperate due to having a different profile of the standard. Vendors can even ignore features that they view as unimportant, yet prevail in the long run. The use of profiles in these ways can force one interpretation, or create defacto standards from official standards. Engineers can design or procure by using a profile to ensure interoperability. For example, the International Standard Profile, ISP, is used by the ISO in their ISO ISP series of standards; in the context of OSI networking, Britain uses the UK-GOSIP profile and the US uses US-GOSIP; there are also various mobile profiles adopted by the W3C for web standards. In particular, implementations of standards on mobile devices often have significant limitations compared to their traditional desktop implementations, even if the standard which governs both permits such limitations. In structural engineering a profile means a hot rolled structural steel shape like an -beam. In civil engineering, a profile consists of a plotted line which indicates grades and distances (and typically depths of cut and/or elevations of fill) for excavation and grading work. Constructors of roadways, railways (and similar works) normally chart the profile along the centerline. A profile can also indicate the vertical slope(s) (changes in elevation) in a pipeline or similar structure. Civil engineers always depict profile as a side (cross section) view (as opposed to an overhead (plan) view).