Lighting definition can be termed as the use of light or luminaire to achieve practical or aesthetic effects. Lighting includes the use of both natural light sources by using natural sources like sunlight, reflections, etc, and artificial and light sources like lamps and light fixtures.
or technically, Light is that part of the electromagnetic spectrum that is perceived by our eyes. The wavelength range is between 380 and 780nm. By day we see in colour, while at night we can only see in shades of grey.
Daylighting (using windows, skylights, or light shelves) is sometimes used as the main source of light during the daytime to save energy in place of using artificial lighting, which represents a major component of energy consumption in buildings. Proper lighting can enhance task performance, improve the appearance of an area, or have positive psychological effects on occupants.
Indoor lighting is usually accomplished using light fixtures and is a key part of interior design. Lighting can also be an important aspect of landscape projects. Lighting designers can help you to get the optimum solution for your lighting requirement with the most efficient, and best lighting design for you, the Lighting Designer is responsible for the design, installation, and operation of the lighting and special electrical effects used in the production
Effects of lighting
Visual functions - Biological effects - Emotional perception
Lighting has three main effects
- Light for visual functions
- Illumination of task area in conformity with relevant standards
- Glare-free and convenient
- Light creating biological effects
- Supporting people’s circadian rhythm
- Stimulating or relaxing
- Light for emotional perception
- Lighting enhancing architecture
- Creating scenes and effects

Basic parameters of lighting
Luminous flux – Luminous intensity – Illuminance – Luminance

1. Luminous flux (Φ )
The luminous flux describes the quantity of light emitted by a light source. The luminous efficiency is the ratio of the luminous flux to the electrical power consumed (lm/W). It is a measure of a light source’s economic efficiency.
Abbreviation: Φ Phi
Unit: lm Lumen

2. Luminous intensity (I)
The luminous intensity describes the quantity of light that is radiated in a particular direction. This is a useful measurement for directive lighting elements such as reflectors. It is represented by the luminous intensity distribution curve (LDC).
Abbreviation: I
Unit: cd Candela

3. Illuminance (E)
Illuminance describes the quantity of luminous flux falling on a surface. It decreases by the square of the distance (inverse square law). Relevant standards specify the required illuminance (e.g. EN 12464 “Lighting of indoor workplaces”).
Illuminance: E(lx) = luminous flux (lm)/area (m2)
Abbreviation: E
Unit: lx Lux

4. Luminance (L)
Luminance is the only basic lighting parameter that is perceived by the eye. It specifies the brightness of a surface and is essentially dependent on its reflectance (finish and color).
Abbreviation: L
Unit: cd/m2
Types of lighting
Direct lighting - Indirect lighting - Direct /indirect lighting - Mellow lighting

Direct Lighting
– Highly directional
– Strong glare reduction at certain angles
– Dark ceiling (cave effect)
– Limited flexibility of workstation layout
– Energy efficiency on the task level

Indirect Lighting
– Diffuse lighting conditions
– Room gains in height
– Glare-free
– Workstations can be positioned anywhere
– Low energy efficiency

Direct / Indirect Lighting
– Pleasant room impression
– High user acceptance
– Good contrast ratios
– Flexible workstation layout
(indirect component > 60 %)

Mellow Light
– Recessed direct/indirect solution
– Workstations can be positioned anywhere
– Glare-free
– Reduced luminance levels at all viewing angles
– Gives an impression of daylight in room
Layers of lighting
Ambient lighting - Accent lighting - Task lighting - Feature lighting

Ambient Lighting
General or ambient lighting is intended to light up a room in its entirety. It provides a uniform level of illumination throughout the space independently of other lighting sources.
Moreover, its purpose is to ensure safe and easy traffic, as well as to create an overview of the room. The ambient light bounces off the walls to illuminate as much space as possible.

Accent Lighting
Accent lighting is used mainly to focus on a specific point of interest or to achieve the desired effect. This type of lighting gives the impression of a larger room. It is more frequently used to highlight an architectural feature, a plant (in outdoor layout), a sculpture, or a collection of objects.

Task Lighting
Task lighting illuminates the tasks a person carries out in a given space such as reading, cooking, computer work. A brighter light is required in a smaller focal point of the room for these sorts of tasks.
For a more pleasant illumination, it is often best to avoid harsh lights or lighting that cast troublesome shadows.

Feature Lighting
Feature lighting refers to lighting that gives the space personality and identity. Feature lighting can refer to the fitting itself which makes the statement whether on or off. Using a pendant in the center of the bedroom can add to comfort levels and make the bedroom feel cozier the pendant can be in the same soft and diffuse aesthetic vein as your table or floor lamps
FAQ about lighting definition, basics & types
What does lighting mean?
What are the 3 types of lighting?
What is importance of lighting?
What are effects of lighting?
Light creating biological effects by supporting people’s circadian rhythm for stimulating or relaxing mood.
Light for emotional perception Lighting enhancing architecture by creating scenes and effects