Use case diagram

[Madhu Juneja]

can someone explain the difference between include, uses, extends that are used in the use case diagrams ?

[Vishakha Ahuja]

The include relationship is used when a number of steps are similar across more than one use case and you don't want to repeat these steps.
The extends is used when you are describing a variation in a use case.

[Giri Prasad]

This is clearly explained in the Fowler book
Include --- is when two are more of ur Use-Cases are using same chunk of behavior , say, some validations are calculations of validity used by different scenarios
Extends --- is adding behavior to a Use-Case at the points it declares as "extention points" . This can be used to handle the alternative scenarios, say , in a shopping cart example handling the Credit Card failure situation
I am not sure of what u r referring to when u said uses.

[Tiger Scott]

uses is similar to the concept of a service. An independent piece which may be accessed by ( and for) multiple use cases. Ex: email, credit card service etc.
HTH

[Giri Prasad]

http://www.fbk.eur.nl/FBK/VG1/JVH/BIM02/SHEETS/c5/tsld021.htm
From what this link says to me uses is sounding same as include. Madhu did u came across any documents that mentions both uses and include??

[Walter Vetrivel]

http://www.fbk.eur.nl/FBK/VG1/JVH/BIM02/SHEETS/c5/sld021.htm