| has gloss | eng: The Framework Class Library (FCL) is a standard library and one of two core components of Microsoft .NET Framework. The FCL is a collection of thousands of reusable classes (within hundreds of namespaces), interfaces and value types. The Base Class Library is a part of FCL and provides the most fundamental functionality, which includes classes in namespaces System, System.CodeDom, System.Collections, System.Diagnostics, System.Globalization, System.IO, System.Resources, System.Text, and System.Text.RegularExpressions. |