Unicast, broadcast, multicast, anycast: who receives the packet and who makes the copies
Every mechanism has a step-by-step animation, the configuration explained line by line and the exam notes. Where a parameter changes the outcome, you get a simulator in which you change it yourself.
TL;DR
Unicast reaches a single host: the switch takes it out a single port by the MAC table, the router by longest prefix match, and ARP is the only moment it needs broadcast. Broadcast reaches everyone in the VLAN and dies at the router; whatever has to cross (DHCP) is rewritten as unicast by ip helper-address. Multicast reaches only the subscribers: IGMP tells the router who wants the group, IGMP snooping tells the switch on which ports, and PIM builds the tree between the source and the receivers, with an RP in sparse mode or without an RP in SSM; everything relies on the RPF check. Anycast is an ordinary unicast advertised from several places — routing chooses the closest instance, and the health check provides the failover. IPv6 keeps three of the four modes and drops broadcast, replacing it with targeted multicast groups.
How to read the notes: red = critical for the exam, green = theory, blue = numbers, yellow = pitfalls, cyan = differences between platforms and standards. In the animations, the configuration lines used in the current step are highlighted automatically; the ← → arrows change the step when the animation is selected.
The analogy, in short
Think of a neighborhood of apartment blocks: a letter with the name on the envelope (unicast), an announcement over the block's intercom, which doesn't reach beyond the block's door (broadcast), a newspaper delivered only to the subscribers on the caretaker's list (multicast) and the emergency number, answered by the closest station (anycast).
The model holds up to §11. From §12 on (VXLAN, mVPN), it breaks; see the full analogy and its limits in §15.