Decompressing

Decompressing is the process of reducing pressure on a system, whether by releasing confinement, expanding a compressed substance, or restoring data to its original form after compression.

In data processing, decompression is the reverse operation of compression. It reconstructs the original data from a compressed representation. Common algorithms include Huffman coding, LZ77, and DEFLATE; formats such as ZIP, gzip, and PNG rely on decompression to retrieve content. Decompression must handle potential errors if compressed data is corrupted or incomplete.

In physical systems, decompressing occurs when a gas or liquid expands as pressure falls. This can produce cooling (or heating in some processes) and may involve valves, regulators, or relief devices. In engineering, decompressing can help manage pressure differentials and protect components.

In diving, decompression describes the staged ascent required to allow inert gases to leave solution safely. Inadequate decompression can lead to decompression sickness. Decompression planning, including stops and ascent rates, is standard practice in professional and recreational scuba.

In medicine and health care, decompression can refer to relief of pressure on tissues, such as surgical decompression of nerves. In everyday life, the term is also used metaphorically to describe taking time to relax and reduce mental or emotional pressure—decompressing after work or travel.