What is the minimum typeface size recommended for maximum visibility in instructional materials?

The recommendation for a minimum typeface size of 18 point for instructional materials is rooted in principles of readability and visibility. This size is generally considered more effective for ensuring that text is easily readable from a distance, which is crucial in instructional settings where the material needs to be visible to a larger audience.

Using an 18 point typeface helps accommodate individuals with varying levels of visual acuity and can reduce eye strain, making it more accessible to a diverse group of learners. Larger type sizes enhance legibility, especially in environments where the audience may be looking at the text from different angles or distances.

In contrast, smaller typeface sizes, such as 12 or 14 points, may lead to difficulty in reading, particularly for those in the back of a classroom or seminar room. A size of 24 point, while still visible, might be excessively large for standard instructional materials, resulting in less content fitting on a page and potentially overwhelming the visual layout. Therefore, the 18 point typeface strikes a balance between visibility and space efficiency, making it the optimal choice for maximum visibility in instructional contexts.