# Close to Metal

> low level GPGPU programming interface

**Wikidata**: [Q2655785](https://www.wikidata.org/wiki/Q2655785)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Close_to_Metal)  
**Source**: https://4ort.xyz/entity/close-to-metal

## Summary
Close to Metal (CTM) is a low-level programming interface and application programming interface (API) designed for general-purpose computing on graphics processing units (GPGPU). Developed by ATI Technologies, it provides minimal abstraction from the hardware, enabling direct control over GPU resources. It is also known by several aliases, including Thin Hardware INterface (THIN) and ATI Stream.

## Key Facts
*   **Developer:** ATI Technologies
*   **Type:** Application programming interface (API) and Low-level programming language
*   **Primary Function:** General-purpose computing on graphics processing units (GPGPU)
*   **Short Name:** CTM
*   **Aliases:** Close-to-the-Metal, THIN (Thin Hardware INterface), Data Parallel Virtual Machine, Technologie ATI Stream™, ATI Stream, Brook+.
*   **Freebase ID:** /m/02pj4nb
*   **Wikipedia Presence:** Available in 9 languages (ar, en, es, fi, fr, ko, pt, ru, uk)
*   **Classification:** Instance of a low-level programming language, providing minimal abstraction from a computer's hardware.

## FAQs
### Q: What is Close to Metal?
A: Close to Metal (CTM) is a low-level GPGPU programming interface developed by ATI Technologies. It is designed to provide minimal abstraction from the hardware, allowing for direct interaction with the GPU.

### Q: What are the alternative names for Close to Metal?
A: It is known by several names and aliases, including CTM, Close-to-the-Metal, THIN (Thin Hardware INterface), Data Parallel Virtual Machine, Technologie ATI Stream™, ATI Stream, and Brook+.

### Q: What is the function of Close to Metal?
A: Its primary use is general-purpose computing on graphics processing units (GPGPU). As a low-level interface, it facilitates tasks that require close interaction with the graphics hardware.

### Q: How does Close to Metal relate to low-level programming languages?
A: Close to Metal is classified as an instance of a low-level programming language. This means it provides little to no abstraction from the hardware, contrasting with high-level programming languages that offer greater abstraction.

## Why It Matters
Close to Metal represents a significant approach to GPU computing by offering a "close to the bare metal" interaction model. In the context of computer science, low-level languages are fundamental because they allow developers to precisely manage system resources and interact directly with the processor. By providing minimal abstraction, CTM enables high-performance applications where direct hardware control is paramount. This capability is crucial for core system components and performance-critical software, bridging the gap between software instructions and hardware execution.

## Notable For
*   **Minimal Abstraction:** Providing a thin hardware interface that offers direct control over GPU resources.
*   **GPGPU Advancement:** Serving as a foundational low-level interface for general-purpose computing on graphics processing units.
*   **ATI Technologies Development:** Being a key proprietary technology developed by ATI Technologies (now AMD) prior to the widespread adoption of open standards like OpenCL.
*   **Versatility:** Being known by a wide variety of names including THIN, ATI Stream, and Brook+, reflecting its evolution and integration into different technology stacks.

## Body

### Definition and Classification
Close to Metal is a low-level GPGPU programming interface and an instance of an application programming interface. It is strictly classified as a low-level programming language, a type of programming language that provides minimal abstraction from a computer's hardware. This classification implies that CTM allows for very direct control over the machine's operations and resources, contrasting with high-level programming languages that offer greater abstraction.

### Development and Identity
The interface was developed by **ATI Technologies**. It is most commonly referred to by its short name, **CTM**, but is also recognized by several other identifiers and aliases:
*   **Close-to-the-Metal**
*   **THIN** (Thin Hardware INterface)
*   **Data Parallel Virtual Machine**
*   **Technologie ATI Stream™**
*   **ATI Stream**
*   **Brook+**

### Technical Context
As a tool for **general-purpose computing on graphics processing units (GPGPU)**, Close to Metal functions similarly to other low-level languages (such as Assembly language, ASSIRIS, BAL, and SUBLEQ) by maintaining a close correspondence to the underlying hardware instructions. This direct correspondence is essential for applications requiring optimized performance and granular control, ensuring that every clock cycle and memory byte is managed efficiently.

### Identifiers and Metadata
*   **Freebase ID:** /m/02pj4nb
*   **Wikipedia Title:** Close to Metal
*   **Sitelink Count:** 9
*   **Wikipedia Languages:** Arabic, English, Spanish, Finnish, French, Korean, Portuguese, Russian, Ukrainian.

## References

1. Freebase Data Dumps. 2013