A data structure is an arrangement of data in a computer's memory or even disk storage. An example of several common data structures are arrays, linked lists, queues, stacks, binary trees, and hash tables. Algorithms, on the other hand, are used to manipulate the data contained in these data structures as in searching and sorting.
Many algorithms apply directly to a specific data structures. When working with certain data structures you need to know how to insert new data, search for a specified item, and deleting a specific item.
Commonly used algorithms include are useful for:
Searching for a particular data item (or record).
Sorting the data. There are many ways to sort data. Simple sorting, Advanced sorting
Iterating through all the items in a data structure. (Visiting each item in turn so as to display it or perform some other action on these items)