Glossary

Concise, sourced definitions of the investing terms used across ETFpedia concepts. Each term is a standalone page that other pages link to.

  1. 01 Advanced Chip Packaging Advanced Chip Packaging · Advanced chip packaging assembles multiple dies into one high-performance package using 2.5D and 3D techniques like CoWoS, TSVs, and hybrid bonding.
  2. 02 Agentic AI Agentic AI · Agentic AI completes multi-step tasks autonomously by planning, calling tools, and acting in a loop, shifting compute demand toward CPUs and inference.
  3. 03 What is an AI accelerator? AI accelerator · An AI accelerator is a chip specialized for neural-network math: GPUs, custom ASICs like Google's TPU, and wafer-scale processors such as Cerebras's.
  4. 04 What is AI displacement immunity? AI Displacement Immunity · AI displacement immunity is how protected a company's earnings are from being copied or automated away by AI, usually thanks to physical assets.
  5. 05 AI Inference AI Inference · AI inference is running a trained AI model to produce an output for each input. It is the recurring, usage-driven counterpart to training a model.
  6. 06 What is a battery energy storage system? Battery Energy Storage System (BESS) · A battery energy storage system (BESS or ESS) stores electricity in battery cells and discharges it on demand, smoothing renewables and meeting peak demand.
  7. 07 What is co-packaged optics? Co-Packaged Optics · Co-packaged optics (CPO) puts optics next to the switch chip to cut power per bit by about 30-40%, a key next-generation AI data-center technology.
  8. 08 What is the Corporate Value-up Program? Corporate Value-up Program (기업 밸류업 프로그램) · The Corporate Value-up Program is Korea's 2024 government initiative pushing listed companies to disclose plans that raise valuations and shareholder returns.
  9. 09 CoWoS CoWoS · CoWoS (Chip-on-Wafer-on-Substrate) is TSMC's 2.5D advanced-packaging platform for AI accelerators. Its capacity gates how many accelerators can ship.
  10. 10 What is data center power? Data Center Power · Data center power is the electricity supply chain behind a data center: grid hookups, transformers, switchgear, busways, backup generation, and storage.
  11. 11 What is a defense offset? Defense Offset · A defense offset is a reciprocal obligation requiring an arms seller to deliver economic value back to the buyer, via technology transfer or local production.
  12. 12 What is downstream space? Downstream Space · Downstream space is the services segment that turns satellite signals and data into communications, navigation, and Earth observation products on the ground.
  13. 13 What is DRAM? DRAM (Dynamic Random-Access Memory) · DRAM is computing's working memory, storing bits as capacitor charge. Three makers dominate it, and it is the building block of HBM and server memory.
  14. 14 What is Earth observation? Earth Observation · Earth observation (EO) is the collection of data about the Earth from satellites, the downstream space segment that sells imagery, monitoring, and analytics.
  15. 15 What is friend-shoring? Friend-shoring · Friend-shoring routes supply chains to trusted allies rather than rivals, a strategy popularized by Janet Yellen to make trade more secure and resilient.
  16. 16 What is GPU-as-a-Service? GPU-as-a-Service (Neocloud) · GPU-as-a-Service (GPUaaS) is a cloud model where neoclouds like CoreWeave, Nebius, and IREN rent large GPU clusters for AI training and inference.
  17. 17 What is HBM? HBM (High Bandwidth Memory) · HBM is DRAM stacked beside a processor and wired through a 2,048-bit interface; HBM4 reaches 2 TB/s per stack, the memory behind AI accelerators.
  18. 18 What is HVDC? High-Voltage Direct Current (HVDC) · HVDC is a transmission technology that moves bulk electricity as direct current at very high voltage, cutting long-distance losses versus AC lines.
  19. 19 What is the holding-company discount? Holding-Company Discount (지주사 디스카운트) · The holding-company discount is the gap between a listed holding company's market value and the value of its stakes; in Korea it has run 30 to 60 percent.
  20. 20 What is a humanoid robot? Humanoid Robot · A humanoid robot is a human-shaped, general-purpose robot, usually bipedal with arms and hands, built to work in spaces and with tools made for people.
  21. 21 IC Package Substrate IC Package Substrate · An IC package substrate is the fine-line board that mounts a chip die and routes its connections out. High-end FC-BGA substrates are an AI packaging chokepoint.
  22. 22 MLCC (Multilayer Ceramic Capacitor) MLCC (Multilayer Ceramic Capacitor) · A multilayer ceramic capacitor (MLCC) stores charge and smooths voltage in circuits. AI servers use far more high-capacitance MLCCs than traditional servers.
  23. 23 What is NAND flash? NAND Flash · NAND flash is the non-volatile memory behind SSDs and storage. Learn how it works, who makes it, and why it matters to the China memory and AI storage themes.
  24. 24 What is on-device AI? On-Device AI · On-device AI runs AI models locally on a phone, PC, or edge device using an NPU, instead of the cloud. It lowers latency, cost, and privacy exposure.
  25. 25 What is physical AI? Physical AI · Physical AI is artificial intelligence embodied in machines that sense and act in the real world, such as robots, as opposed to screen-bound generative AI.
  26. 26 What is Physical Asset Intensity? Physical Asset Intensity · Physical Asset Intensity is the share of a company's value tied to tangible, capital-intensive assets like PP&E, a core screen for asset-heavy concepts.
  27. 27 What is satellite communications? Satellite Communications · Satellite communications (satcom) delivers voice, data, and broadband through orbiting satellites, the largest downstream segment of the space economy.
  28. 28 What is silicon photonics? Silicon Photonics · Silicon photonics builds optical components onto a silicon chip to move data with light at high bandwidth and lower power, a core AI data-center technology.
  29. 29 Silicon Wafer Silicon Wafer · A silicon wafer is the thin disc of single-crystal silicon that chips are fabricated on, the raw substrate at the base of the semiconductor supply chain.
  30. 30 What is a small modular reactor? Small Modular Reactor (SMR) · A small modular reactor (SMR) is a nuclear reactor of about 300 MWe or less, built from factory-made modules to cut cost and time versus conventional reactors.
  31. 31 What is a solid-state battery? Solid-State Battery · A solid-state battery replaces the liquid electrolyte of a lithium-ion cell with a solid one for higher energy density and safety, the next-gen EV cell.
  32. 32 What is a TPU? TPU (Tensor Processing Unit) · A TPU is Google's custom AI accelerator chip, co-designed with Broadcom and made by TSMC, tuned for the matrix math behind neural networks.
  33. 33 What is upstream space? Upstream Space · Upstream space is the segment that designs, builds, and launches rockets, satellites, and spacecraft, the capital-intensive supply side of the space economy.
  34. 34 Wafer-Fab Equipment (WFE) Wafer-Fab Equipment (WFE) · Wafer-fab equipment (WFE) is the machinery that turns blank silicon wafers into patterned chips: lithography, deposition, etch, CMP, and process control.