Hi, I am an intermediate user of Excel 2010 but this is a really basic question for which I cannot find any information about . I have never used the Custom properties tab found within “Info, Properties, Advanced Properties. Can someone please explain why you would use the dropdown fields of Text, Date, Number, Yes or No and give examples or tell me where I can source this information. I know this is used to identify workbooks but I would love to know how to use this and why I would be using this. Thanks