What are these called in ASP.NET?
<%# ... %><%= ... %><%: ... %>
And what are the different variations? How are each of them used?
What are these called in ASP.NET?
<%# ... %><%= ... %><%: ... %>And what are the different variations? How are each of them used?
The generic term for the tags like <% %> is "nuggets", with the exception of <%@ %> which is called a directive.
How each nugget is used can be found at .NET "code nugget blocks"?.
That's a code block. The version with the # is used for data binding. They basically allow you to embed C# code into your aspx page.
MSDN has a good article on code blocks here, and a good article on data binding expressions here.