/store/book/author $.store.book[*].author the authors of all books in the store
//author $..author all authors
/store/* $.store.* all things in store, which are some books and a red bicycle.
/store//price $.store..price the price of everything in the store.
//book $..book the third book
$..book[-1:] the last book in order.
$..book[:2] the first two books
//book[isbn] $..book[?(@.isbn)] filter all books with isbn number
//book[price<10] $..book[?(@.price<10)] filter all books cheapier than 10
//* $..* all Elements in XML document. All members of JSON structure.