Yesterday I stuck in yet another discussion of what portable really means. Word becomes more popular but is often used too easily. Most software called that is not really portable at all. But what portable is?
Software may need
- Installation. Most of software comes as packaged setup file that must be installed.
- Frameworks. Applications based on specific frameworks require those installed.
- Libraries. Software may require specific DLL files or even specific versions of those. In best case they are included with software. If not and it is assumed that libraries are common and present in the system it easily creates DLL hell scenario.
- Local resources. Program may need to use local resources like hard drive space to create temporary files.
- User rights. Software that interacts with system in potentially dangerous way may need administrator's permission to run. Having such is usual case for home PCs but not work environment.
- Specific Windows version(s). Windows is known to have excellent backward compatibility. But version prior to 2000 lack Unicode support (which is common aspect of modern apps). Also Vista created degree of forward incompatibility.
Software may create
- Driver. Stuff that works with hardware often does that.
- Temporary files. Leftovers created during performing some tasks.
- Registry entries. Used for storing settings or just for the heck of it.
- Files in user's profile folder. Storing settings or just making hunting for temporary files harder.
- Most recently used entries. Traces of what documents were opened with app.
- File associations. Registering some file types to open with itself.
And portable is?
Portable software is not requiring or doing anything of the listed above.
Realistically there are few grades of what people call portable.
- Works without installation. Such software can be simply copied and run on the system. But it interacts with the system in pretty much any way and is often indistinguishable from usual apps.
- Generally portable. Most common - such software can be run from external media and doesn't require things that most of computers doesn't have.
- Self-destructing. It comes as self-extracting archive that unpacks to temporary folder, runs from there and deletes those unpacked files at shutdown.
- Self-contained. This is purest of portable. Self-contained software doesn't require anything, works on every Windows version (after 98 at least) and leaves no traces in the system. It may create temporary stuff but in that cases there is cleaning routine performed on shutdown.
Lesson to learn
If you are looking for portable don't be fast to believe developer's description. It is there to convince you. Read :
- reviews from blogs that value portable highly (like mine);
- editorial reviews from software portals;
- sites that specialize in portable.
Portable Freeware Collection is good place to start and it includes specifics about portable grade in descriptions.