About .NET Framework
Since CDBurnerXP 4, we use the Microsoft .NET Framework 2.0 (or any higher version) as basis for our application.
If you are running Windows Vista or Windows 7, you already have .NET 3.0 preinstalled so there is nothing to care about. Any earlier operating system, however, requires that you install it manually.
Which one to choose? .NET 3.5 is the most current version which allows you to run .NET applications of any kind, .NET 2.0 is the most lightweight version (smallest size). Choose whatever you prefer.
Alternatives
Some people seem to hate the .NET Framework for whatever reason, for those we have a reduced CDBurnerXP runtime package based on .NET 2.0 (thanks to Hacker Harry for creating it).
Before you install CDBurnerXP, download and “execute” the following registry file: dotnet2.reg
After CDBurnerXP is installed, install the CDBXP runtimes, into the same directory as CDBurnerXP.
Mono
Mono is an open source alternative to .NET, with support for other platforms, including Microsoft Windows. You might have the idea to try Mono to run CDBurnerXP, however, it does not work and probably will never work.