*Its All about Pj Problem Strings -
7 Spaces Of Interest and their associated Basic Sequences; 7 Pj Problems of Interest (PPI) and their Alleles (A)*

The word *system* is ubiquitous in design and analysis parlance. Basically, a *system* is the *space* under consideration. Everything outside the considered *space* is called its *surrounding*. Almost always, the *space* is occupied by *matter*. A *system* may be as simple as an atomic space or as immense as the entire Universe. The definition of a perimeter inorder to establish the *space* to be considered is a *containership problem* and any problems of interest in the *space* being considered are definitely *Pj problems*.

The number of systems that can be defined is infinite: atomic systems, molecular systems, ecosystems, respiratory system, digestive system, cardiovascular system, health systems, political systems, economic systems, social systems, etc. Fortunately, the grouping of systems is finite. Any *system* with respect to the definition of its *containership*, explicitly belong to one of the following 7 *space groups*:

*single-matter static space*

*single-matter dynamic space*

*multi-matter static space*

*multi-matter dynamic space*

*multi-matter multi-static spaces*

*multi-matter multi-dynamic spaces*

And the problems of interest in it, belong to the *Pj problems* group.

*Systems* designs and analyses are in essence S_{i}P_{j} designs and analyses (where S_{i} is the ith space under consideration and P_{j} is the jth problem of interest in the space).

The *system* parlance is opaque in the sense that it does not enunciate the basic concepts of a *system*. The concepts of *space*, *matter* and *dynamism* are familiar and can easily be explained even to unseasoned thinkers. So are the members of the *Pj problems* group.