w3schools is good place to start learning web technologies
before reading any other manual or book. Here I am summarizing
the relation among most of XML flavors. I’ll recommend it before
starting with w3schools. In addition of above diagram, - DTD &
XSD both do the same job. But XSD is newer than DTD, in form of
XML, and has more datatypes & other options. - You need not to
launch XSLT explicitly to see how your XSL will output finally.
XSLT comes with Internet browser. So you just open your XML in
browser. It’ll read linked XSL and will display output
accordingly. - XSL-FO can be considered as next version of XSL.
*Editor : I used eclipse for developing all XML flavours. HTML
vs XHTML XHTML is nothing but XML formatted HTML. You need to
follow XML rules nothing else. Like - proper nesting of tags -
all tags must be closed - there must be a root tag - value of an
attribute must be enclosed in double quote - tags name,
attributes name and their values must be in low case. - etc. . .