Algorithm

Algorithm

An informal description:

An algorithm is any well-defined computational procedure that takes some values as input and produces some values as output. An algorithm is thus a sequence of computational steps that transforms the input into the output.

A more formal definition:

An algorithm is an ordered set of unambiguous, executable steps that defines a terminating process.

Data Structure

In computer science, a data structure is a particular way of storing and organizing data in a computer so that it can be used efficiently.

Different kinds of data structures are suited to different kinds of applications, and some are highly specialized to specific tasks. For example, B-trees are particularly well-suited for implementation of databases, while compiler implementations usually use hash tables to look up identifiers.

Data structures are used in almost every program or software system. Data structures provide a means to manage huge amounts of data efficiently, such as large databases and internet indexing services. Usually, efficient data structures are a key to designing efficient algorithms. Some formal design methods and programming languages emphasize data structures, rather than algorithms, as the key organizing factor in software design.