- E L E C T R O N I C S - Pictures used for cover art: 1. https://pixabay.com/illustrations/technology-network-connection-3357605/ 2. https://pixabay.com/illustrations/blockchain-network-business-3448502/ 3. https://pixabay.com/illustrations/technology-background-geometric-4237426/ all three of them by Pete Linforth aka TheDigitalArtist (Pixabay license)