In the topics of graphs we cover state-charts which is a type of graph tat simulate transitions and states of different process. It is composes of state which are rectangles and transitions are arrows. A transition describes a change of active state which is triggered by an event or action and may set off other actions. There are two types of states either AND or XOR.
• AND decomposition captures the property that when a system is in a given state, it must also be in all substates of that state. It has several substates. Control is assumed by all substates.
• XOR decomposition captures the property that when a system is in a given state, it must be in exactly one of the substates of that state. Represented subdividing the box of the containing state with a dashed line and placing concurrent substates on either side of the line. Control is assumed by the default substate