Technology
Audio decoder converts digital audio to analog form
Binary decoder, digital circuits such as 1-of-N and seven-segment decoders
Decompress (compression decoder), converts compressed data (e.g., audio/video/images) to an uncompressed form
Instruction decoder, an electronic circuit that converts computer instructions into CPU control signals
Quadrature decoder, converts signals from an incremental encoder into counter control signals
Video decoder, converts base-band analog video to digital form
Music
Decoder (band), a defunct post-hardcore band that was briefly named Lead Hands
Decoder (duo), a drum and bass duo
Decoder (album)