cross compatibility : Java Glossary

If you write a progam, ideally it would run or every computer, past, present and future. Cross compatibility is concerned with whether a program will run on other computers of the current generation. Java aims for WORA (Write Once, Run Anywhere) but defects in the various JVMs (Java Virtual Machines) or run times might make a program not run well on some particular program. More commonly, the problem is there simply is no version of the program for a given platform. If a developer creates a program for Windows, he has a huge effort to rewrite it for the Mac or Linux. Where programs that don’t have a visual interface can often be ported just by tweaking some constants and running the code through that platform’s compiler. A big part of porting is retesting the program to make sure any transformations it underwent to make it work on a different platform did not break or impair it.