A simple interactive visualization of the selection-sort algorithm: https://en.wikipedia.org/wiki/Selection_sort.
I'm using the pico-8 color palette for the graphics: https://www.romanzolotarev.com/pico-8-color-palette/.
You will need love2d to use this program. Download here: https://love2d.org/. Once installed just drag and drop the visualization folder onto the love2d application.
Use left and right arrow-keys to move the cursor, up and down arrows to increment or decrement the number under the cursor. Press x at any point to start or stop sorting.