Question

When using the inbuilt template for my html pages in eclipse, I get the following code appended prior to xhtml doctype: <?xml version="1.0" encoding="ISO-8859-1" ?> Does this code affects the html pages?

Answer 1

No it doesn’t, your html is still valid and readable for every browser. (However, it will put IE into quirks mode for every version below IE9 — see @Rob’s comment.)

Because you are using xhtml, which is basicly a type of xml, the browser needs some kind of encoding for the document.

See w3c:

Historically, the character encoding of an HTML document is either
specified by a web server via the charset parameter of the HTTP
Content-Type header, or via a meta element in the document itself. In
an XML document, the character encoding of the document is specified
on the XML declaration (e.g., <?xml version="1.0"
encoding="EUC-JP"?>). In order to portably present documents with
specific character encodings, the best approach is to ensure that the
web server provides the correct headers. If this is not possible, a
document that wants to set its character encoding explicitly must
include both the XML declaration an encoding declaration and a meta
http-equiv statement (e.g., <meta http-equiv="Content-type"
content="text/html; charset=EUC-JP" />). In XHTML-conforming user
agents, the value of the encoding declaration of the XML declaration
takes precedence.

BTW this is only if you use another char-set than UTF-8 or UTF-16. If you use default UTF8 or UTF016 there are some exceptions. See W3C (again).