To start off, the Joshua Tree Epiphany is the application and recognition of four basic design principles that help make up a good design. This theory was developed by a designer named Robin Williams. The four basic design principles that make up a good design include contrast, repetition, alignment, and proximity.
Contrast refers to the arrangement of opposite elements such as colors, textures, shapes, sizes, fonts, etc to create visual interest and drama. This means avoiding elements on a page that are similar to one another. For contrast to be effective in a design, it must be strong and very different.
Repetition refers to repeating visual elements such as colors, shapes, sizes, textures, lines, image, font, etc to create rhythm and unify an effect of a design. This means repeating elements throughout an entire design. Almost any elements can be used in repetition as well.
Alignment refers to the arrangement of elements in correct relative positions to other elements. This means visually connecting elements with each other in a design relative to a line or margin. Doing this allows things to be arranged in a way that matches how people naturally scan a design, balance the design in a visually appealing way, and creates a visual connection between related elements.
Proximity refers to the Universal Principles of Design that states that elements that are close together are typically perceived to be more related than elements that are further apart from each other. This means related items in a design should be close together. It can show the viewer visual clues to understand the organization of a design.
The Joshua Tree Epiphany is applied to current websites through these principles. For example, let’s look at the Digital Media and Multimedia Design website.

The site uses contrast using the white background vs black and grey text and logo. It creates natural contrast due to the color of the background and the text and logo being vastly different so it naturally captures the viewers’ eyes. It uses repetition with the font and the text being in all caps. It uses alignment by aligning all the text where it belongs like with the title and the area where all the links and redirects are. It uses proximity with the the area for links and redirects by having all of them close together and away from the title so that the viewer is aware that this area is where all the redirects to other areas of the site would be.