"If—", the Rudyard Kipling poem

If (island), a small island in the Bay of Marseille, France

Initiation factor, an important component in protein synthesis

Interactive fiction, text-based computer games featuring interactive stories and environments

Impact Factor, a measure of the importance of scientific journals

In Flames, a melodic death metal band from Sweden

if...., a 1968 cult film starring Malcolm McDowell

IF? Records, a Tokyo-based electronic music label

If and only if, iff, indicating necessary and sufficient conditions

If..., a political comic strip which appears in the UK newspaper The Guardian

Immunofluorescence, a form of labeling substances with radioactive antibodies

Intelligent falling, alternative theory of gravitation

Intermediate filament, a component of the cytoskeleton

InvisionFree, an Internet service provider

If..., a series of BBC drama-documentaries

IF (x86 flag), the Interrupt Flag in the x86 architecture

If (magazine), subtitled "Worlds of Science Fiction"

Intelligent Finance, a bank

if..., a 1994 video game in the Shin Megami Tensei series for the Super Famicom

"If" (song), any of several songs

International Forum Design (iF), a society best-known for its iF design awards

Islas Airways (IF is its IATA airline designator)

If (insurance company), in the Nordic countries

Intermediate frequency, an intermediate step in radio transmission or reception

IFF, Iff or iff can stand for: if and only if, a mathematical and logical connector indicating that either both statements are true or both are false Identification friend or foe, an electronic radio based identification system utilizing transponders In...

Internal focusing, a lens technology in which focusing occurs only with internal elements

If?, a dance band of the late 1980s and early '90s

If is a very common English word used in the protasis of a conditional sentence and the antecedent of a proposition. It is often used in computer languages to indicate a conditional. If is also