Sholes arranged the keys in their odd fashion to prevent jamming on mechanical typewriters by separating commonly used letter combinations.
Your digital footprint is the trail of 'electronic breadcrumbs' you leave behind when you use the internet. It can include the websites you visit, the photos you upload and your interactions with other people on social networks.
I believe they are icons.
Computational thinking inclines invokes the techniques of decomposition, latter reconstruction, abstraction & algorithms development