wix - heat.exe generate an id of directory

by heat was generated code like

<DirectoryRef Id="TARGETDIR">

<Directory Id="dir77AA1A0808D9092357CFE6C2BECDEE70" Name="files" />

please, tell w开发者_StackOverflow中文版hat is this strange Id of directory. i want to copy dll in applicationfolder. should i change this id to something like INSTALLDIR?

it looks like a GUID, ie a unique identifier for a directory referenced elsewhere in your wix project.

You can change it, but if you do make sure you change all references to that identifier.