As our referenced quote states in SFMZ's Sci-Fi Subgenres A to Z feature, Cyberpunk Sci-Fi is noted for its focus on "high tech and low life" and taking its name from the combination of cybernetics and punk. Characters are sometimes modified to 'jack' their brain directly into cyberspace.
These tales are typically set on Earth, and involve a hacker immersed in a cyber-world, interacting (both on line and physically) with similar people. It's often set in a high-tech, often bleak, mechanistic and futuristic universe of computers, hackers, and computer/human hybrids.
It features advanced technology such as information technology coupled with some degree of breakdown in the social order. Cyberpunk often encompasses nanotechnology, androids, virtual reality, and/or a warning as to what could possibly go wrong if technology falls into the wrong hands.
Classic cyberpunk characters were marginalized, alienated loners who lived on the edge of society in generally dystopic futures where daily life was impacted by rapid technological change, an ubiquitous datasphere of computerized information, and invasive modification of the human body.
Humans may have built-in computer jacks or software, and spend considerable time "living" in a virtual environment. When mainstream fans think cyberpunk, likely they would think The Matrix, but perhaps better examples of this subgenre would be Ghost in the Shell and Johnny Mnemonic.
Films released before 1984 should be seen as precursors to the genre. Cyberpunk Sci-Fi includes the following sub-sets, visit the SFMZ link above for their descriptions:
CYBERSPACE SCI-FI and POST-CYBERPUNK SCI-FI.
BIOPUNK is a spinoff of the 'cyberpunk' subgenre, involving hackers or government agencies who manipulate human DNA. Though many stories about cybernetics and artificial intelligence fall into this category, most biopunk focuses on genetic and biological manipulation.