Cat5e (1G/100m), Cat6 (10G/55m), Cat6a (10G/100m), Cat7 (shielded, 10G+). Fiber: Single-mode (long distance, yellow cable), Multi-mode (shorter distance, orange/aqua cable).
Cat6a is the current standard for new installations (supports 10G at full 100m). Single-mode fiber for inter-building/campus. Multi-mode for within building. Know the speed/distance limits for certification exams. Plenum-rated cable required in air-handling spaces (fire safety).