Knocking or Knockin or Knockin' may refer to: *

Knocking (2006 film) ''Knocking'' is a 2006 documentary film directed by Joel Engardio and Tom Shepard that focuses on the civil liberties fought for by Jehovah's Witnesses. It focuses primarily on the stories of three Jehovah's Witnesses, and how their lives demons ...

, a documentary about Jehovah's Witnesses *

Knocking (2021 film) ''Knocking'' () is a 2021 Swedish thriller film directed by Frida Kempff and written by Emma Broström, based on a short story by Johan Theorin. The film stars Cecilia Milocco, Krister Kern, Albin Grenholm, Ville Virtanen, and Alexander Salzb ...

, a Swedish thriller film *

Engine knocking In spark-ignition internal combustion engines, knocking (also knock, detonation, spark knock, pinging or pinking) occurs when combustion of some of the air/fuel mixture in the cylinder does not result from propagation of the flame front ignite ...

, or the sound accompanying automotive combustion malfunction *

Port knocking In computer networking, port knocking is a method of externally opening ports on a firewall by generating a connection attempt on a set of prespecified closed ports. Once a correct sequence of connection attempts is received, the firewall rules ...

, a covert method of opening a port on a server *

Roof knocking Roof knocking (; Arabic: صاروخ تحذيري) or "knock on the roof" is a term used by the Israel Defense Forces (IDF) to describe its practice of dropping low-yield devices on the roofs of targeted civilian homes in the occupied Palestinian t ...

, a bombing practice of the Israeli Defense Forces *

Gene knockin In molecular cloning and biology, a gene knock-in (abbreviation: KI) refers to a genetic engineering method that involves the one-for-one substitution of DNA sequence information in a genetic locus or the insertion of sequence information not fou ...

, genetic engineering method *

Knockin Castle Knockin Castle is situated in the village of Knockin on Shropshire between Oswestry and Shrewsbury (), England. This was a fortified residence on level ground founded by Guy le Strange between 1154 and 1160 and it remained the principal holding ...

, castle situated in the village of Knockin on Shropshire between Oswestry and Shrewsbury *Knocking, Austria, a hamlet, subdivision of

Erlauf (municipality) Erlauf is a municipality in the district of Melk in the Austrian state of Lower Austria Lower Austria ( , , abbreviated LA or NÖ) is one of the nine states of Austria, located in the northeastern corner of the country. Major cities are Amstet ...

in Austria *"Knockin'", a 1995 song by Spanish band

Double Vision Diplopia is the simultaneous perception of two images of a single object that may be displaced in relation to each other. Also called double vision, it is a loss of visual focus under regular conditions, and is often voluntary. However, when occ ...

See also