什么是web.config或app.config中的编译标记？

Question

我注意到compilation中有一个web.config部分，如：

<compilation debug="false" targetFramework="4.5.2">
  <assemblies>
    <add assembly="DevExpress.ExpressApp.Xpo.v15.2, Version=15.2.9.0, Culture=neutral, PublicKeyToken=b88d1754d700e49a" />
    <add assembly="DevExpress.ExpressApp.v15.2, Version=15.2.9.0, Culture=neutral, PublicKeyToken=b88d1754d700e49a" />
    <add assembly="DevExpress.ExpressApp.Web.v15.2, Version=15.2.9.0, Culture=neutral, PublicKeyToken=b88d1754d700e49a" />
    <add assembly="DevExpress.Persistent.Base.v15.2, Version=15.2.9.0, Culture=neutral, PublicKeyToken=b88d1754d700e49a" />

它是为了什么？这些组件在哪里添加？