returns the text string xyz where x, y, z are three randomly independent digits, while:
returns nnn where n is a random digit repeated three times.
Here Calc converts each number given by ROUND(RAND()*10)) to text before concatenating.
CONCATENATE("Print Date: " ; TEXT(TODAY();"dddd, d mmmm yyyy"))
returns Print Date: Thursday, 1 January 2009 (assuming today's date was Jan 1, 2009). This example serves to demonstrate that you can combine functions in quite complex ways. This example is made up of the date function TODAY() which returns the current date as a number (NOTE: Jan 1, 2009 is represented as 39814) and the text function TEXT() which allows you to format the numeric representation of the date in a [useful] textual format.