The @ grammar

With a profile working with all applications is sometimes not ideal for everything. MacType allows you to customize almost everything on an executable or group based style.

How

With a regular section like [general] works for everything application, mactype also accepts a section formatted like [general@notepad.exe] which applies only to programs with the name notepad.exe (no path verification)

Under the [X@notepad.exe] section, not all options need to be reassigned. Only the ones that need customization are required, all the other omitted options will be read from the global [X] section.

E.g. with a profile like

[General]
Name=Default
HookChildProcesses=1
HintingMode=1
AntiAliasMode=4
NormalWeight=16
RenderWeight=1.4

[General@notepad.exe]
RenderWeight=2

For notepad.exe, it behaves exactly like a profile as

[General]
Name=Default
HookChildProcesses=1
HintingMode=1
AntiAliasMode=4
NormalWeight=16
RenderWeight=2 

Limitation

The @ grammar works on almost all the sections except for

UnloadDll

ExcludeModule

IncludeModule

as they are read before an application starts to run and are not effective to the rendering result.