2. Package Naming

By convention, a package's name is the same as the last element of its import path. For instance, the math/rand package comprises files that begin with:

rand.go

package rand

That said, package names aren't required to match their import path. For example, I could write a new package with the path github.com/textio/rand and name the package random:

random.go

package random

While the above is possible, it is discouraged for the sake of consistency.

One Package / Directory

A directory of Go code can have at most one package. All .go files in a single directory must all belong to the same package. If they don't, an error will be thrown by the compiler. This is true for main and library packages alike.