One of the more important cable topics that every engineer must be aware of, are the different types of aircraft cable classifications. For instance the differences between British and United States (U.S.) cable classification systems where British cables are classified by Minimum breaking load in hundred weight (cwt) and American cables by size and minimum breaking load in pounds ( lbs. ).
Cables are constructed by strands, There are usually seven strands to a standard cable except 3cwt cable, which has only 4 strands, A strand is in turn made up of wires preformed in a spiral shape suited to the strand. A typical strand could be made up of 7 or 19 wires.
A strand is pre-formed so as to resist the adverse straightening effects that high loadings have within control cables
If we take a cable construction of 7×19 we can say that the cable has 7 strands and each strand has 19 wires.