Professional standards provide specifications for, among other things, quality, performance, composition, safety, and/or interoperability. Standards are often designed by experts from a variety of areas, including academia, corporations, non-profit organizations, and they may be local, national, or global in scope.
Meeting appropriate standards in your project signify a level of quality, and some standards, called codes, have legal force. Similarly, using components that meet a particular standard are an indication that they will perform as advertised.
Locating standards can be difficult, and reading standards moreso. However, in order for components to work together correctly, and so that your customer will believe in your product, standards are important to the success of your project.