An algorithm is simply a solution to a problem. An algorithm presents the solution to a problem as a well defined set of steps or instructions. Pseudo-code is a general way of describing an algorithm. Pseudo-code does not use the syntax of a specific programming language, therefore cannot be executed on a computer. But it closely resembles the structure of a programming language and contains roughly the same level of detail.
An algorithm gives a solution to a particular problem as a well defined set of steps. A recipe in a cookbook is a good example of an algorithm. When a computer is used for solving a particular problem, the steps to the solution should be communicated to the computer. This makes the study of algorithms a very important part in computer science. An algorithm is executed in a computer by combining lot of elementary operations such as additions and subtractions to perform more complex mathematical operations. But translating the idea of the algorithm in to computer code is not straight forward. Specially, converting an algorithm in to a low level language such as assembly language could be very tedious than using a high level language such as C or Java. When designing an algorithm, it is important to do an analysis on the resources (such as time and storage) required by the algorithm. Notations such as big O notation are used for performing time and storage analysis on algorithms. Algorithms can be expressed using natural languages, pseudocode, flowcharts, etc.
Pseudocode is one of the methods that could be used to represent an algorithm. It is not written in a specific syntax that is used by a programming language and therefore cannot be executed in a computer. There are lots of formats used for writing pseudocodes and most of them borrow some of the structures from popular programming languages such as C, Lisp, FORTRAN, etc. Also, natural language is used when presenting details that are not important. Most of the algorithms are presented using pseudocode since they can be read and understood using programmers who are familiar with different programming languages. Some languages such as Pascal have syntax that is very similar to pseudocode making the transformation from pseudocode to the corresponding program code easier. Pseudocode allows to include control structures such as WHILE, IF-THEN-ELSE, REPEAT-UNTIL, FOR, and CASE, which are present in many high level languages.
What is the difference between Algorithm and Pseudocode?
An algorithm is a well defined sequence of steps that provides a solution for a given problem, while a pseudocode is one of the methods that can be used to represent an algorithm. While algorithms can be written in natural language, pseudocode is written in a format that is closely related to high level programming language structures. But pseudocode does not use specific programming language syntax and therefore could be understood by programmers who are familiar with different programming languages. Additionally, transforming an algorithm presented in pseudocode to programming code could be much easier than converting an algorithm written in natural language.