It makes one consider the appropriate etiquette for advising those who have passed along a virus along with their data. We have, on occasion, alerted people to a virus on their systems. We tried to provide suggestions for clearing the infection. The usual response is gratitude and appreciation. A significant proportion of the population is colour blind.
Affected individuals are unable to perceive differences between certain colours.
This could impair a person's ability to observe the difference between normal text and hyperlinked text on a web page, for example. This is a good reason why text links on web pages should be underlined as well as coloured. The underlining might be the only cue a colour blind person has that a certain word or words are clickable. By the same token, underlining should be used sparingly, and better yet not at all, for any text on a web page that is not a hyperlink. Let's give as much help as possible to the colour-blind among us.