November 5, 2025

A comprehensive reference guide for data center, cloud, network, and digital infrastructure professionals.

⚡ Power, Electrical & Mechanical Infrastructure

AC – Alternating Current
DC – Direct Current
UPS – Uninterruptible Power Supply
VRLA – Valve-Regulated Lead-Acid (battery type)
LIB – Lithium-Ion Battery
BESS – Battery Energy Storage System
GENSET – Generator Set (diesel or natural gas)
N+1 – Redundancy: one spare component for every N
N+2 / 2N / 2N+1 – Higher redundancy levels
ATS – Automatic Transfer Switch
STS – Static Transfer Switch
RPP – Remote Power Panel
PDU – Power Distribution Unit
ePDU – Intelligent / Metered PDU
MCC – Motor Control Center
MOP – Method of Procedure (especially for power ops)
LOTO – Lock Out / Tag Out
HV – High Voltage
MV – Medium Voltage
LV – Low Voltage
MVA – Mega Volt-Amperes (transformer rating)
MW – Megawatt
kW – Kilowatt
KVA – Kilovolt-Ampere
PF – Power Factor
HIS – High-Integrity Switchgear
SCADA – Supervisory Control and Data Acquisition
PMS – Power Monitoring System
EMS – Energy Management System
BMS – Building Management System
MEP – Mechanical, Electrical, Plumbing
AHJ – Authority Having Jurisdiction (building inspectors)

❄ Cooling, Environmental & Thermal Systems

CRAC – Computer Room Air Conditioner
CRAH – Computer Room Air Handler
DX – Direct Expansion cooling
CHW – Chilled Water
CW – Condenser Water
CT – Cooling Tower
AHU – Air Handling Unit
FCU – Fan Coil Unit
MAU – Make-Up Air Unit
IEQ – Indoor Environmental Quality
PUE – Power Usage Effectiveness
DCiE – Data Center Infrastructure Efficiency
EER – Energy Efficiency Ratio
SEER – Seasonal Energy Efficiency Ratio
WUE – Water Usage Effectiveness
CUE – Carbon Usage Effectiveness
D2C – Direct-to-Chip Liquid Cooling
CDU – Coolant Distribution Unit
CDX – Coolant Distribution Exchange
TCS – Thermal Control System
HPC Cooling – High-Performance Compute Cooling (liquid/immersion)
HVAC – Heating, Ventilation & Air Conditioning
CFD – Computational Fluid Dynamics (modeling airflow)
VFD – Variable Frequency Drive

📡 Network, Fiber & Interconnection

ISP – Internet Service Provider
MSP – Managed Service Provider
CDN – Content Delivery Network
IX / IXP – Internet Exchange Point
ASN – Autonomous System Number
BGP – Border Gateway Protocol
DNS – Domain Name System
DHCP – Dynamic Host Configuration Protocol
MPLS – Multiprotocol Label Switching
DWDM – Dense Wavelength Division Multiplexing
CWDM – Coarse Wavelength Division Multiplexing
OTN – Optical Transport Network
PoP – Point of Presence
LOA – Letter of Authorization (cross-connect)
MRC – Monthly Recurring Charge
X-Connect – Physical interconnection between two parties
LAG – Link Aggregation Group
QoS – Quality of Service
QoE – Quality of Experience
VPN – Virtual Private Network
VLAN – Virtual LAN
NIC – Network Interface Card
MTU – Maximum Transmission Unit
NOC – Network Operations Center
SOC – Security Operations Center

🏢 Data Center Types, Services & Operational Models

DC – Data Center
MTDC – Multi-Tenant Data Center
Colo – Colocation
Hyperscale – Large-scale cloud provider data center
Edge DC – Edge / local low-latency facility
Modular DC – Prefabricated or containerized data center
HPC – High-Performance Computing
AI DC – AI-optimized data center (GPU dense)
Hot Aisle / Cold Aisle – Airflow containment patterns
RLO – Remote Lights-Out (fully automated DC ops)
ITSM – IT Service Management
RFS – Ready for Service
RFD – Ready for Design
RFT – Ready for Tenant
MTTR – Mean Time to Repair
MTBF – Mean Time Between Failures
SLT – Site Lead Technician
MOP – Method of Procedure
SOP – Standard Operating Procedure
EOP – Emergency Operating Procedure

📊 Finance, Leasing & Commercial Metrics

REIT – Real Estate Investment Trust
NOI – Net Operating Income
FFO – Funds From Operations
AFFO – Adjusted Funds From Operations
EBITDA – Earnings Before Interest, Taxes, Depreciation & Amortization
EBITDAre – REIT-adjusted EBITDA
GAAP / IFRS – Accounting standards
CAPEX – Capital Expenditures
OPEX – Operating Expenses
IRR – Internal Rate of Return
ROI – Return on Investment
NPV – Net Present Value
TCO – Total Cost of Ownership
LOI – Letter of Intent
MSA – Master Services Agreement
SLA – Service Level Agreement
Churn – Percentage of customers leaving
Backlog – Booked but not yet revenue-generating deals
MRR – Monthly Recurring Revenue
ARR – Annual Recurring Revenue
PPU – Price per Unit (kW or cabinet)
PPM – Price per Month
Rate Card – Pricing schedule

🔐 Security, Compliance & Certifications

SOC 1 / SOC 2 / SOC 3 – Compliance audits
ISO 27001 – Information Security Standard
ISO 50001 – Energy Management Standard
PCI-DSS – Payment Card Industry Data Security Standard
HIPAA – Health Insurance Portability and Accountability Act
FISMA – Federal Information Security Management Act
HSM – Hardware Security Module
IDS – Intrusion Detection System
IPS – Intrusion Prevention System
EDR – Endpoint Detection & Response
SIEM – Security Information & Event Management
IAM – Identity & Access Management
MFA – Multi-Factor Authentication
RBAC – Role-Based Access Control
SOC – Security Operations Center
GRC – Governance, Risk & Compliance

🖥 Hardware, Compute & Storage

CPU – Central Processing Unit
GPU – Graphics Processing Unit
TPU – Tensor Processing Unit
ASIC – Application-Specific Integrated Circuit
FPGA – Field-Programmable Gate Array
DIMM – Dual In-Line Memory Module
NVMe – Non-Volatile Memory Express
SSD – Solid State Drive
HDD – Hard Disk Drive
RAID – Redundant Array of Independent Disks
SAS / SATA – Storage interfaces
RPM – Revolutions per Minute (disk speed)
U / RU – Rack Unit (1U = 1.75 inches)
ToR – Top of Rack switch
EoR – End of Row switch
MoR – Middle of Row switch
PDU – Power Distribution Unit
Blade – Thin server module

🌍 Sustainability, Energy & Environmental

PPA – Power Purchase Agreement
REC – Renewable Energy Credit
ESG – Environmental, Social, Governance
GHG – Greenhouse Gas
SBTi – Science Based Targets initiative
LEED – Leadership in Energy and Environmental Design
ZNE – Zero Net Energy
EaaS – Energy-as-a-Service
DER – Distributed Energy Resources
DG – Distributed Generation
EV – Electric Vehicle (impacting grid planning)
DR – Demand Response
VPP – Virtual Power Plant

🏗 Construction, Real Estate & Development

EPC – Engineering, Procurement & Construction
GC – General Contractor
RFP – Request for Proposal
RFQ – Request for Quote
ROW – Right-of-Way
FAR – Floor Area Ratio
SWPPP – Storm Water Pollution Prevention Plan
NEC – National Electrical Code
IBC – International Building Code
AHJ – Authority Having Jurisdiction
CUP – Conditional Use Permit
SUT / SUP – Special Use Permit
ZTA – Zoning Text Amendment
Site Plan – Local development application
Use Permit – Governing document for construction type
COD – Commercial Operation Date

☁ Cloud, Virtualization & Software

AWS – Amazon Web Services
Azure – Microsoft Cloud
GCP – Google Cloud Platform
OCI – Oracle Cloud Infrastructure
IaaS – Infrastructure as a Service
PaaS – Platform as a Service
SaaS – Software as a Service
VM – Virtual Machine
VPC – Virtual Private Cloud
API – Application Programming Interface
K8s – Kubernetes
DNS – Domain Name System
SDN – Software-Defined Networking
NFV – Network Function Virtualization