NESL is a parallel programming language

Programming language

A programming language is an artificial language designed to communicate instructions to a machine, particularly a computer. Programming languages can be used to create programs that control the behavior of a machine and/or to express algorithms precisely....

 developed at Carnegie Mellon by the SCandAL project and released in 1993. It integrates various ideas from parallel algorithm

Parallel algorithm

In computer science, a parallel algorithm or concurrent algorithm, as opposed to a traditional sequential algorithm, is an algorithm which can be executed a piece at a time on many different processing devices, and then put back together again at the end to get the correct result.Some algorithms...

s, and functional programming and array programming

Array programming

In computer science, array programming languages generalize operations on scalars to apply transparently to vectors, matrices, and higher dimensional arrays....

languages.

The most important new ideas behind NESL are

• Nested data parallelism: this feature offers the benefits of data parallelism, concise code that is easy to understand and debug, while being well suited for irregular algorithms, such as algorithms on trees, graphs or sparse matrices.
• A language based performance model: this gives a formal way to calculate the work and depth of a program. These measures can be related to running time on parallel machines.

The main design guideline for NESL was to make parallel programming easy and portable. Algorithms are typically significantly more concise in NESL than in most other parallel programming languages, and the code closely resembles high-level pseudocode.