3Technical elements

• 3.1Information Design and UX (Universal Design, UX/UI, Accessibility, Human Interfaces)

  Learn universal design, which aims for products usable by everyone; the distinction between UX (user experience), which designs the overall experience, and UI (user interface), which designs the operable screen; accessibility, ensuring information is reachable regardless of disability; human interfaces (GUI, voice UI, gesture input) covering human-machine interaction; and structuring information (menu hierarchies, card sorting) so users can understand it easily.

• 3.2Information Media (Compression, Encoding, Image/Audio/Video, VR/AR/CG)

  Learn the distinction between lossless compression and lossy compression for reducing data size; representative formats JPEG, PNG, MPEG, and MP3; the three stages of digitizing analog information—sampling, quantization, and encoding; VR (virtual reality), which lets users experience a virtual space, versus AR (augmented reality), which overlays information onto the real world; and CG, computer-generated and computer-processed imagery.

• 3.3Databases (Relational Model, Normalization, SQL, Transactions, Concurrency Control, Failure Recovery)

  Learn the relational model, which handles data as tables; normalization (first through third normal form), which eliminates redundancy and update anomalies; SQL (SELECT, JOIN, GROUP BY) for manipulating tables; the primary key, which uniquely identifies a row, and the foreign key, which references another table; the transaction, which groups multiple operations as a unit (the ACID properties); concurrency control (locking, deadlock) for managing simultaneous access; rollback and roll-forward for recovering from failures; and where NoSQL fits in.

• 3.4Networks (OSI/TCP-IP Layers, IP Addressing, DNS/DHCP, Protocols, Bandwidth Calculation)

  Learn the OSI reference model, which organizes communication into layers, and the layers used in practice by TCP/IP; IP addresses and subnet masks, which identify devices on a network; routing, which chooses a path; DNS for name resolution and DHCP for automatic address assignment; representative protocols such as HTTP/HTTPS, SMTP, POP, and IMAP; LANs (wired Ethernet and wireless LAN); and the frequently tested skill of bandwidth/transfer-time calculation.