Cubicles are "modular", in the sense that they can be used in a variety of different applications. Many office cubicle manufacturers design them with customization in mind.
One company's needs often varies greatly from that of another. Each component of the cubicle, from the panels to the worksurfaces, to the electrical connections can be personalized to the end user's specific requirements.
Each cubicle part has the capability to be customized to a specific application. For example, the height of the cubicle panel can have a great effect on the worker's interaction with other cubicle workers and his or her environment. To illustrate further, a workstation panel that is taller (69" for example), will separate one worker from another - and from visual distractions. Additionally, a tall panel will somewhat help sheild the occupant from other noises.
On the other hand, a cubicle with panels that are 42" tall will allow the cubicle residents to see (and hear) other users when the person is in the seated position. Many cubical manufacturers have designed a variety of heights and widths of modular cubicle panels in order to satisfy the needs of the purchaser.