You know the word palimpsest? It is one of my favorites. It refers to a document on which more recent writing appears over older writing. The intent of such writing isn’t defined by the term itself–sometimes the newer writing is meant to deface the older writing (as with graffiti), sometimes to supplement it (as with JJ Abrams’ new book) but many times it is meant to explain or explicate what it is written over.
The practice is old and useful. We all know it from our own experience as students for when we took notes, or received them, in the margins of our books or on the papers we submitted for evaluation. Those notes, or added visual direction of arrows and underlines written overtop the original copy of a then-scanned and re-copied section of a textbook, could be so helpful. Digital media has turned our margins into dynamic wrappers on which our ballpoint pens no longer work, but with applications like Monosnap and Skitch we can still write in the margins, or directly overtop, of whatever we can pull up on our computer screens.
Since I use Monosnap, that is the application I’ll show here. However, I believe Skitch has a similar, if not the same, toolset (with the added benefit, potentially, of being integrated into Evernote).
Above is a bit of an Escher trick: I monosnapped the monosnap window that appears after I monosnap. Effectively, the app gives the user two options for capturing whatever is onscreen–a fullscreen screenshot, or a region specified screenshot that you draw with crosshairs. These function much like the integrated screenshot tools that you find on any Mac, with the difference that, after the screenshot is taken, the above window pops up. Within the window you’re given a myriad of options for how you may annotate the image you’ve just taken. It’s fast and easy to make notes for your students, for yourself, or for the heck of it.
Both applications are free for their core functionality (which is all I ever use), with, I believe, some additional tools available if you wish to purchase them.