Meaning in graphics work
A raster image represents a picture as a grid of pixels, each carrying colour information. Photographs and many scanned artworks use this form of representation.
Raster content differs from vector shapes, whose geometry is described mathematically. A PDF can contain both, so its file extension does not establish that every object scales cleanly.
Example and practical consequence
A company logo saved as a small screenshot may be raster even when it originated as vector artwork. Enlarging that screenshot for a sign can expose its limited detail.
Inspect the actual objects, placed size and available source information. Request the original permitted artwork when useful, and distinguish intentional pixel effects from unwanted loss of clarity. File conversion into a PDF or SVG wrapper does not turn a low-detail image into equivalent vector geometry.
Take it to the next job
- Identify raster objects before evaluating enlargement or asking for source files.
