another stack analogy is the tasks you perform during typical workday you're busy on long-term project ( )but you're interrupted by coworker asking you for temporary help with another project (bwhile you're working on bsomeone in accounting stops by for meeting about travel expenses ( )and during this meeting you get an emergency call from someone in sales and spend few minutes troubleshooting bulky product (dwhen you're done with call dyou resume meeting cwhen you're done with cyou resume project band when you're done with you can (finally!get back to project lower priority projects are "stacked upwaiting for you to return to them placing data item on the top of the stack is called pushing it removing it from the top of the stack is called popping it these are the primary stack operations stack is said to be last-in-first-out (lifostorage mechanismbecause the last item inserted is the first one to be removed the stack workshop applet let' use the stack workshop applet to get an idea how stacks work when you start up the appletyou'll see four buttonsnewpushpopand peekas shown in figure the stack workshop applet is based on an arrayso you'll see an array of data items although it' based on an arraya stack restricts accessso you can' access it as you would an array in factthe concept of stack and the underlying data structure used to implement it are quite separate as we noted earlierstacks can also be implemented by other kinds of storage structuressuch as linked lists figure the stack workshop applet