If you have professionally developed any type of application, then you must have had the requirement to "deploy" it. For example, if you are developing a Windows (desktop) application, you may have been asked to create a setup.exe
for it – which in Visual Studio is a deployment project. If you are a web application developer, you can similarly add a "web setup project" and/or deploy your files in a CAB file (a special type of ZIP/compressed) file. Or perhaps you have experience with using MSI (windows installer) files. Regardless, when it is time to hand off your application to others you must "package" it for deployment.
SharePoint at its heart is an ASP.NET web application, so SharePoint understands special installer files called Solutions
(creative name, right?). SharePoint solution files have the extension .wsp
and are simply in CAB (compressed) format. The great news is that Visual Studio 2010 will automatically "package" your SharePoint customizations in WSP...