Advanced packaging technologies enable heterogeneous integration by connecting multiple dies with different functions, process nodes, or materials in a single package. Chiplet architectures decompose monolithic SoCs into smaller functional blocks (compute, I/O, memory) that can be manufactured separately and integrated through advanced packaging. This approach enables mix-and-match of dies from different process nodes—for example, combining 3nm logic chiplets with 7nm I/O dies and HBM memory stacks. Interposers provide high-density interconnects between dies, while 3D stacking uses through-silicon vias (TSVs) for vertical connections. Advanced packaging offers better yield (smaller dies have higher yield), design reuse, faster time-to-market, and cost optimization by using appropriate process nodes for each function. Technologies include 2.5D packaging with silicon interposers (CoWoS, EMIB), 3D stacking with TSVs, and fan-out wafer-level packaging. Challenges include thermal management, signal integrity across die boundaries, and testing. Advanced packaging is critical for AI accelerators, high-performance computing, and mobile SoCs.