The manifesto lists principles. Principles must be implemented and turned into processes in order to actually produce software. Scrum's daily stand-up is a process, a tool, to implement the following principle:
"The most efficient and effective method of
conveying information to and within a development
team is face-to-face conversation."
And it also contributes to this one:
"The best architectures, requirements, and designs
emerge from self-organizing teams."
Agile is defined here: http://agilemanifesto.org/