The parts you can see
The face is the front surface that gives a letter its shape. The return is its side wall, which gives it depth. A back closes or supports the assembly. The precise construction depends on whether the letter lights through its face, behind the body, or both.
Fabricated bodies are often metal, while light-transmitting faces may be acrylic or polycarbonate. Solid acrylic constructions and flat-cut lettering are other options. The material name alone does not tell you how a letter is lit or attached.
The parts you should ask about
Lighting components, wiring and power supplies need a place to live and a way to be serviced. Their specification affects durability, even illumination and maintenance. Ask your supplier to identify the proposed components and what is included with the sign.
A raceway is a shared enclosure behind the letters. A backer panel is a broader surface that supports the composition. Individual direct mounting can give a clean result, but wiring and fixing locations must be resolved for each letter.
Why choose dimensional lettering?
Separate letters can follow a custom wordmark and let the building show between the characters. They offer a choice of lighting direction, material finish and depth. They are useful when the business identity needs a strong physical presence.
They also need planning. Narrow strokes can limit construction. Electrical access may be difficult. A landlord may require a particular mounting method. Work through those constraints while the design is still easy to change.
Make the first decisions in order
Begin with the location, main viewing direction and existing artwork. Choose the lighting effect next, then review material and mounting. Set the final dimensions with the supplier after checking the wall and any applicable permissions.
To prepare a visual brief, use the studio and export your chosen configuration. A rendering is useful for discussion; the approved production drawings are what resolve the build.