There are many National Standards, but overall the [International organisation for standardisation]?, based in Geneva, Switzerland has established tens of thousands of standards covering almost every coneivable topic. Most of these are then adopted world-wide replacing all the incompatible 'home-grown' standards. Many of these standards are naturally evolved from those designed in-house within an industry, or by a particular country, whilst others have been built from scratch by groups of experts who sit on various Technical Committees.
The [ISO Web Site] describes more of the work that ISO does.
Many ISO Standards are used within the Internet... the most well-known being ISO 8601, ISO 3166 and ISO 8859.