Elements, both in Fire, Water and Visual Studio, works with Projects inside of a Solution. You can think of a Solution as a container for one or more related projects, often called a project group or a workspace in other IDEs.
Fire, Water and Visual Studio will always open a solution, not a project – even if that solution only contains a single project. When you open a
.elements (or legacy
.oxygene) project file directly, the IDE will check if there's a solution (
.sln) file with the same name next to it, or else automatically create a solution file for you.
EBuild, our build toolchain, is capable of building either a Solution or an individual project file.
Solution files use the
.sln file extension, and just like Elements projects files, they are compatible between Fire, Water and Visual Studio (the file format is defined by Microsoft for Visual Studio, and Fire honors the same format). They are plain text files, but you will not normally want to edit them directly unless you really know what you are doing, as the file format is not well-designed for human readability.