If your work is original you get to own copyright even if you don’t have a copyright symbol on it. Pretty much anything qualifies even if it’s not a great art piece. Copyright lasts for the lifetime of the author + 70 years after their death.
Copyright involves the right to stop reproduction or adaptations by others, however does not apply to ideas or info, rather the original expression of these ideas. like all property, ownership of works can be transferred, sold or obtained legally.
Copyright in works may include: literary, dramatic, musical, & artistic – (includes everything from paintings to photos to architectural plans.)
Non works may include: sound recordings, films, broadcasts & published works.
A Creative Commons licence in essence gives permission to anyone who wants to use a particular piece of work as long as they adhere to given conditions such as attribution, (acknowledging the original author of the work) Non commercial, (only the original author is permitted to make money off the given work, no derivatives, (modifying or adapting the original work is not allowed) and share alike (in which, if somebody wishes to share the work, they must do it under the same conditions as the original author)
There are many different combinations of conditions under which an author may share their work, allowing more or less freedom for those who want to use it.