In the Details: Distinguishing Form Labels
A question was posed to the IxDA discussion list about whether or not colons should be used between a label and a form field. The answer is no, and the reasoning is very straightforward.
Colons have been used to separate labels from values because there does need to be something to distinguish one from the other. In black and white print, the colon serves this purpose quite well. On screen, there are many ways to separate a label from a value, including text color, background color, weight, space, etc. Only one or two distinctions need be made. So, for example, if I set the label in gray text, the value in black text, and align the labels in one column and the values in another, that is enough differentiation.
When dealing with form fields, there is already a significant visual distinction between labels and values. The values are contained within boxes. Thus, a colon, to use Tufte’s terminology, is unnecessary, non-data ink that just adds visual clutter to the form.
