Front-end knowledge - Control displaying and hiding div tags

1      // attachment hide information list 
2      var tAppendixDiv = document.getElementById ( "AppendixDiv" );
 . 3      tAppendixDiv.style.display = "none";

1      // The accessories display list 
2      var tAppendixDiv = document.getElementById ( "AppendixDiv" );
 . 3      tAppendixDiv.style.display = "Block";

These are all the more important, to use in the project.