DAC
Abbreviation with 3 meanings
| Stands for | Digital-to-analog converter |
|---|---|
| Meanings | 3 |
| Categories | Technology & Computing, Science & Engineering |
DAC has three meanings. The most common are Digital-to-analog converter (consumer electronics) and Direct air capture (environmental); it can also stand for Discretionary access control.
Meanings of DAC at a glance
| # | DAC stands for | Context |
|---|---|---|
| 1 | Digital-to-analog converter | Technology & Computing › Consumer Electronics |
| 2 | Direct air capture | Science & Engineering › Environmental |
| 3 | Discretionary access control | Technology & Computing › Cybersecurity |
1. Digital-to-analog converter
Technology & Computing · Consumer Electronics Abbreviations · also used in science
Circuit that converts digital audio data into the analog electrical signal that drives headphones and speakers. Every phone, computer and TV contains one; audiophiles buy external DACs for cleaner sound.
Example: My phone has no headphone jack, so I use a USB-C DAC dongle with my wired headphones.
When Apple removed the headphone jack from the iPhone 7 in 2016, its Lightning adapter had to include a tiny DAC. Specifications such as signal-to-noise ratio and total harmonic distortion indicate quality, though differences between decent DACs are often inaudible. Wireless headphones contain their own DAC after the Bluetooth decoder.
2. Direct air capture
Science & Engineering · Environmental Abbreviations
Technology that removes carbon dioxide directly from ambient air using chemical filters or solutions, after which the CO2 can be stored underground or used. Because air contains only about 0.04% CO2, DAC needs much energy and currently costs several hundred dollars or more per tonne.
Example: The Iceland DAC plant pairs its fans with geothermal energy and stores the CO2 in basalt rock.
Swiss company Climeworks opened Orca in Iceland in 2021, designed to capture 4,000 tonnes a year, and the larger Mammoth plant in 2024. US projects such as Stratos in Texas aim for hundreds of thousands of tonnes a year. In electronics DAC means digital-to-analog converter.
3. Discretionary access control
Technology & Computing · Cybersecurity Abbreviations
Lets the owner of a file or resource decide who else may access it, as with ordinary Unix permissions and Windows file sharing. The model is flexible, but mistakes or malware running as the owner can spread access easily.
Example: Under DAC, any user can make their home folder world-readable with one chmod command.
Defined in the US Department of Defense's "Orange Book" (TCSEC, 1983) alongside mandatory access control. Most consumer operating systems use it by default, adding mandatory controls for sensitive components. In audio hardware DAC means a digital-to-analog converter.
Related abbreviations
More consumer electronics abbreviations
- CD – Compact Disc
- CEC – Consumer Electronics Control
- CES – Consumer Electronics Show
- CRT – Cathode-ray tube
- DLNA – Digital Living Network Alliance
- DLP – Digital Light Processing
- DSLR – Digital single-lens reflex
- DTS – Digital Theater Systems
See all 104 consumer electronics abbreviations →