In brief
Photography is light made into memory, evidence, art, desire, surveillance, family history, public proof, and private ache. Tate defines photography as the process or practice of creating a photograph: an image produced by the action of light on light-sensitive material. Digital photography has changed the material process, but the older truth remains useful. Photography begins with light meeting a receiving surface.
That receiving surface is never innocent. A photograph is made by a device, a point of view, a selection, a technology, a body, and a culture of looking.
Definition
Photography is the practice of creating images by recording light, historically on light-sensitive materials and now also through digital sensors and computational processes. It differs from painting through its optical and technical relation to a moment before the lens, from cinema through its stillness, and from memory through its external record, though it can alter memory profoundly.
A photograph may be documentary, artistic, scientific, intimate, commercial, forensic, devotional, political, or experimental.
Why this matters
Photography changed the sensual relation between image and time. It allowed a face, gesture, wound, street, meal, protest, artwork, or landscape to be held after the moment passed. It also gave images a special claim to truth: the camera was there.
That claim is powerful and limited. Photographs can document reality, but they can also crop, stage, manipulate, aestheticize, exploit, or mislead. Digital editing and generative media make this distinction even more important.
Photography, intimacy, and distance
A photograph can bring the absent close. It can keep the dead visible. It can preserve a child's hand, a lover's posture, a grandmother's kitchen, a city's vanished light. It can also distance the viewer from the subject by turning suffering, beauty, or poverty into consumable image.
The sensual question is not only what the photograph shows. It is what kind of relation the photograph establishes between viewer and subject.
The ethics of being seen
Photography involves consent, context, ownership, and exposure. A body photographed in one setting may circulate into another. A private image can become public harm. An archival image can restore erased history or repeat the violence by which it was first taken.
For this reason, photography belongs in the encyclopedia not only as an art, but as an ethical practice of attention.
What this changes
To look at a photograph well is to ask: What has light recorded? What has framing removed? Who controlled the image? What does this photograph ask me to feel, and what does it prevent me from knowing?
Photography teaches that seeing can preserve, seduce, accuse, mourn, and distort. The camera does not free us from interpretation. It intensifies our responsibility for it.