our gives access to a variable having package-wide scope.   Well, sort of ...   From perldoc -f our:

“our” associates a simple name with a package variable in the current package for use within the current scope.   When “use strict ‘vars’” is in effect, “our” lets you use declared global variables without qualifying them with package names, within the lexical scope of the “our” declaration.   In this way "our differs from “use vars,” which is package scoped.

Unlike “my,” which both allocates storage for a variable and associates a simple name with that storage for use within the current scope, “our” associates a simple name with a package variable in the current package, for use within the current scope.   In other words, “our” has the same scoping rules as “my,” but does not necessarily create a variable.