# About version number in install desittination folder

Today I installed RAD Studio 10.4, The default installation folder is C:\Program Files (x86)\Embarcadero\Studio\21.0\.

(1) Why the RAD Studio version is 10.4, but the version in folder is 21.0, not 10.4?

(2) If 10.4.1 released in future, after upgrade, the folder will still be C:\Program Files (x86)\Embarcadero\Studio\21.0\ or will changed to C:\Program Files (x86)\Embarcadero\Studio\21.1\ ?

(3) If I uninstall RAD Studio 10.4, then install 10.4.1, the folder will be C:\Program Files (x86)\Embarcadero\Studio\21.0\ or will changed to C:\Program Files (x86)\Embarcadero\Studio\21.1\ ?

• 1) That's due to the number of actual Delphi releases, as over the years they have changed the numbering system (Delphi 7, Delphi 2006, Delphi XE, Delphi Sydney etc)

2) It may change to 21.1 but in the past incremental releases (such as 10.3.1, 10.3.2) have overwritten each other and all go in the 20.0 sub-directory, for example, as they can't co-exist on the same computer

3) If they follow the same pattern as before, then expect it to be the 21.0 directory

• Why the RAD Studio version is 10.4, but the version in folder is 21.0, not 10.4?

RAD Studio is an extension of its predecessor, Borland Developer Studio (BDS).  RAD Studio 10.4 is BDS 21.0, which in turn is Delphi/C++Builder 27.0 (that is why BPLs in 10.4 have a 270 suffix in their names). See Delphi Release Dates for which release corresponds to which version numbers.

If 10.4.1 released in future, after upgrade, the folder will still be C:\Program Files (x86)\Embarcadero\Studio\21.0\ or will changed to C:\Program Files (x86)\Embarcadero\Studio\21.1\ ?

It will still be 21.0.  Update versions are not added to the folder name.

If I uninstall RAD Studio 10.4, then install 10.4.1, the folder will be C:\Program Files (x86)\Embarcadero\Studio\21.0\ or will changed to C:\Program Files (x86)\Embarcadero\Studio\21.1\ ?

Same thing as above.  It will be 21.0