this diagram shows that an orange is somehow associated with basket and that an apple is also somehow associated with barrel association is the most basic way for two classes to be related uml is very popular among managersand occasionally disparaged by programmers the syntax of uml diagram is generally pretty obviousyou don' have to read tutorial to (mostlyunderstand what is going on when you see one uml is also fairly easy to drawand quite intuitive after allmany peoplewhen describing classes and their relationshipswill naturally draw boxes with lines between them having standard based on these intuitive diagrams makes it easy for programmers to communicate with designersmanagersand each other howeversome programmers think uml is waste of time citing iterative developmentthey will argue that formal specifications done up in fancy uml diagrams are going to be redundant before they're implementedand that maintaining these formal diagrams will only waste time and not benefit anyone depending on the corporate structure involvedthis may or may not be true howeverevery programming team consisting of more than one person will occasionally has to sit down and hash out the details of the subsystem it is currently working on uml is extremely useful in these brainstorming sessions for quick and easy communication even those organizations that scoff at formal class diagrams tend to use some informal version of uml in their design meetings or team discussions furtherthe most important person you will ever have to communicate with is yourself we all think we can remember the design decisions we've madebut there will always be the why did do thatmoments hiding in our future if we keep the scraps of papers we did our initial diagramming on when we started designwe'll eventually find them useful reference this howeveris not meant to be tutorial in uml there are many of these available on the internetas well as numerous books available on the topic uml covers far more than class and object diagramsit also has syntax for use casesdeploymentstate changesand activities we'll be dealing with some common class diagram syntax in this discussion of object-oriented design you'll find that you can pick up the structure by exampleand you'll subconsciously choose the uml-inspired syntax in your own team or personal design sessions our initial diagramwhile correctdoes not remind us that apples go in barrels or how many barrels single apple can go in it only tells us that apples are somehow associated with barrels the association between classes is often obvious and needs no further explanationbut we have the option to add further clarification as needed [