State is the attribute values of a thing at a given moment.
A State can be seen as a snapshot of values at a precise moment.
A entity may have several related primary state stored in a attribute called status that forms together a lifecyle.
Code is easy,
State is hard
- File: if a line was added to a file, the file has a new state
- Variable: if a variable has a new value, the variable has a new state
- A on/off button has two states:
Tracking the changes to values as your program runs and propagating this change is called reactive programming.
Automata models computing devices or machines through state transition. See Automata - State