Designing orthogonal software systems

In geometry, two Euclidean vectors are orthogonal if they are perpendicular (form a right angle of 90 degrees). The two vectors meet at the origin point, but do not intersect. The two vectors are independent of each other:

Software that is well designed is orthogonal in that its modules are independent of each other. Ideally, changes to one module in a software system should not require changes to another module. Software systems will undergo many changes during their lifetime and designing them with this in mind provides a number of benefits, including increased productivity for those who work on them and lowered risk of introducing defects when changes are made. Designing orthogonal systems may have higher upfront costs, but over time, a highly maintainable and extendable system will be worth it.

Orthogonal systems are designed so that their elements are loosely coupled and highly cohesive. Let's look at the concepts of coupling and cohesion in more...