Hi Vassili,
See the basic difference between c:set and jsp:useBean is:
c:set is a JSTL tag
while jsp:useBean is a JSP action.
Second thing, you can use jsp:useBean either to retrieve a bean or create a bean object.
While c:set is used to set the property of an already existing bean not to create a bean or get a bean. c:set works somewhat similar to jsp:setProperty action for
java beans.
And third thing,
there is no scope attribute for c:set(when you are using it with
target attribute) JSTL tag as it is there for jsp:useBean JSP action.
And if you provide the value of target attribute as an EL expression, searching is from most restrictive scope to least restrictive scope.
Regards,
Khushhal