HCI Web Application (Theory)

Web ApplicationLearning Outcome4.2.1 Describe the differences between web applications and native applications.4.2.2 State and apply usability principles in the design of web applications. Awebapplicationisanapplicationstoredataremoteserverthatrequiresawebbrowserasaclient to run and internet for data/resource transfer. Whereas,a native/desktopapplicationis an applicationdesignedto servestandalonemachinesthatdon’t requiretheinternetforitsoperation.ExampleofdesktopapplicationsareMicrosoft Words, Microsoft Excel, Notepad. Web Applications Native Applications/Desktop Application Deployment and maintenance (updates) for aweb-based application require deployment ona single set of server machines. Deployment and any maintenance/patch aredone on individual client machinesseparately. Web applications can be accessed fromanywhere (most locations), so there is nolocation constraint. As desktop are confined to a standalonemachine, so they can be only accessed fromthe machines they are deployed in. Web applications are platform-independent,they can work in different types of platformswith the only requirement of a web browser. Desktop applications need to be developedseparately for different platform machines.(Windows, Linux, Unix, Mac etc) Web applications are at higher security risksas they are inherently designed to increaseaccessibility. Desktop applications, on the other hand,have better authorization and administratorshave better control, hence more secure. Web applications rely heavily on internetconnectivity, fortheiroperation. Desktop applications don’t require theinternet for their operations. Someapplications just require internet connectivityat the time ofupdates. Web Application Usability Principles

Webapplicationsaredesignedtoprovideaccesstoinformationandservicesforavarietyofusersfromdifferentbackgrounds.Usabilityisoneimportantfactorforthequalityofawebapplication. It is defined by 5 quality components:● Learnability:whentheusersfirstencounterthewebapplication,howeasyisittolearntonavigate in the system to perform basic tasks?● Efficiency: how fast can the users perform tasks after knowing the system?● Memorability:if theusershavenotusedthesystemfora longtime,howeasyisit torecall the functionality of the system without relearning?● Errors:possibleerrorsthatusersmake,andhowthesystemhelpuserstorecoverfromerrors?● Satisfaction: how pleasant is it for use? Webapplicationsareproductswithoutmanualsandwedon’t expectpeopletobepatienttofigureouthowtheapplicationworks.It hasbecomeaverypopularmarketingplatformforbusinessandcompaniesputusabilityon toppriorityto attractcustomers.Onlineretailwebsite also needs to be explicit and easy to use for more efficient transactions.Human-computerinteractionexpertshas developedplentyof principles,Nielsen’s 10principles,Norman’s rules,Tognazzini’s 16principlesandShneiderman’s 8 goldenrules.Theycoversalltheimportantrulesbutdiffersinthewayhowrulesareorganized.Herewewill discuss Nielsen’s 10 principles developed by Jacob Ni