Basically this depends on your needs and skills, which I don’t know. So I try to give a general advice.
XApplication is a good starter, which gives you quick results without programming. Try the XAppllication tutorial in the online documentation.
If you know programming and your prefered programming language is Java, you should use the Tamino API for Java. There are plenty of samples in the online documentation.
If VisualBasic or C++ is your area, use the HTTP Client API for Activex.
And for JScript, there is the HTTP Client API for JScript.
The last two APIs only work in a Windows ebvironment.
Checkout the online documentation for samples and explanation for the APIs and Tamino in general.
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