Occasionally, there will be a feature along the lines of "Whenever the user selects some text, we will pop up an X." And then I have to remind them about so-called selection readers.
Selection readers are people who habitually select text in a document as they read it. It can be quite maddening looking over the shoulder of a selection reader, because you will see seemingly-random fragments of text get selected, and for those who are selection-deselection readers, the text will almost immediately get cleared. It's like the entire document is blinking with selections. (Other variations of the selection reader are the double-click reader who double-clicks words on the page, the margin-click reader who clicks in the margin, and the hover reader who merely hovers the mouse without clicking.)
There are a number of theories behind why some people are selection readers.
- It's a nervous habit to keep one's fingers occupied, similar to spinning a pen.
- It marks one's place in the document.
- It gives a sense of accomplishment as one progresses through the document.
- It helps the eye follow the reading location in the document during a scroll operation.
I am not a selection reader, but I do click in the document with some regularity. I do this for two reasons.
- To give focus to the document area, so that scrolling the mouse wheel or hitting PgDn will scroll the document text.
- To place the caret inside the viewport.
The second reason needs some explanation.
The caret is the blinking line that shows where your next typed character will be inserted. You can scroll the document so much that the caret goes out of the viewport. For example, if you never click in the document but merely scroll through it, the caret will be at the top of the document, even though you are reading page 25 of 50.
And then you hit PgDn thinking that you're scrolling down one screen, but instead you're going to the middle of page one. Congratulations, you just lost your place and jumped backward 24 pages.
Furthermore, there are some programs which are really twitchy about the caret. If you manage to scroll the caret off screen, they will say, "Sure, go ahead and scroll the caret off screen," but then you breathe on the program funny (say, by switching to another program, then switch back with Alt+Tab), and it says, "Whoa, your caret is waaaaay off screen! Let me help you by scrolling the caret back on screen. No need to thank me. Just helping out."
Of course, what those programs ended up doing is ripping me from page 25 back to page one.
That's why I consciously click in the document a few times after every scroll operation. It's not yet a habitual operation, so I will sometimes forget, and then just my luck, that's the time I accidentally hit PgDn or ↓ or Alt+Tab and get teleported backward in the document.