The Top 100 Three-Letter Acronyms (TLAs) Every Business Should Know in IT

TLA

Stands For

What It Means

IT

Information Technology

The use of computers to store, retrieve, transmit, and manipulate data.

MFA

Multi-Factor Authentication

Adds extra layers of login security beyond just a password.

VPN

Virtual Private Network

Creates a secure connection over the internet to protect data in transit.

DNS

Domain Name System

Translates website names (like google.com) into IP addresses.

IPT

IP Telephony

Voice communication using internet protocol networks.

DMZ

Demilitarised Zone

A security buffer zone between a private network and the internet.

AV

Anti-Virus

Software that detects and removes malicious software.

EDR

Endpoint Detection and Response

Advanced threat detection and response on individual devices.

SIEM

Security Information & Event Management

Collects and analyses security data in real time.

SOC

Security Operations Centre

A team that monitors and responds to cyber threats 24/7.

BEC

Business Email Compromise

A type of phishing attack that targets companies via email fraud.

DLP

Data Loss Prevention

Stops sensitive data from leaving the company network.

IAM

Identity and Access Management

Ensures only the right users can access the right resources.

AD

Active Directory

Manages user access to systems and data in Windows environments.

ACL

Access Control List

Determines who can access or modify resources in a network.

API

Application Programming Interface

Allows software programs to talk to each other.

APT

Advanced Persistent Threat

A prolonged, targeted cyberattack.

BGP

Border Gateway Protocol

Controls how data is routed between large networks.

CAD

Computer-Aided Design

Software used for designing products or buildings.

CPU

Central Processing Unit

The ‘brain’ of a computer.

CRM

Customer Relationship Management

Software to manage interactions with customers.

CSV

Comma-Separated Values

A simple file format used to store tabular data.

CTO

Chief Technology Officer

Senior executive responsible for technology strategy.

DAC

Discretionary Access Control

A system where the data owner decides who has access.

DBA

Database Administrator

Manages and maintains databases.

DDR

Double Data Rate

A type of fast computer memory.

DFS

Distributed File System

Allows access to files across multiple locations.

DHCP

Dynamic Host Configuration Protocol

Automatically assigns IP addresses to devices.

DLP

Data Loss Prevention

Tools that stop data breaches or leaks.

DNSSEC

DNS Security Extensions

Protects DNS from tampering.

DRP

Disaster Recovery Plan

A strategy for restoring operations after a cyberattack or failure.

ERP

Enterprise Resource Planning

Software to manage day-to-day business activities.

FAT

File Allocation Table

A file system for organising data on disks.

FDE

Full Disk Encryption

Encrypts everything on a hard drive.

FTP

File Transfer Protocol

Used to transfer files over the internet.

GPO

Group Policy Object

Centralised way to control user settings in Windows.

GUI

Graphical User Interface

Visual way to interact with computers (menus, icons).

HTML

HyperText Markup Language

The standard language for web pages.

HTTP

HyperText Transfer Protocol

Transfers web content between servers and browsers.

HTTPS

Secure HTTP

Encrypted version of HTTP – protects your data online.

IDS

Intrusion Detection System

Monitors networks for suspicious activity.

IPS

Intrusion Prevention System

Detects and blocks cyber threats.

IoT

Internet of Things

Devices connected to the internet, like smart thermostats.

IP

Internet Protocol

The rules that govern internet addressing and routing.

ISP

Internet Service Provider

The company that gives you internet access.

ITSM

IT Service Management

How IT services are delivered to end-users.

LAN

Local Area Network

A network within a small geographic area (e.g., office).

LDAP

Lightweight Directory Access Protocol

Used to access and maintain directory info.

MDM

Mobile Device Management

Secures and manages smartphones and tablets in a business.

MFA

Multi-Factor Authentication

Requires multiple forms of ID before granting access.

NAS

Network Attached Storage

A device that provides file storage over a network.

NAT

Network Address Translation

Allows multiple devices to share one IP address.

NDR

Network Detection & Response

Monitors and responds to threats at the network level.

OEM

Original Equipment Manufacturer

A company that makes parts for another company’s product.

OS

Operating System

Software that manages computer hardware.

OTP

One-Time Password

A temporary password valid for one login.

PAM

Privileged Access Management

Controls and monitors access to critical systems.

PDF

Portable Document Format

A universal file format for documents.

PST

Personal Storage Table

File type used by Microsoft Outlook.

QoS

Quality of Service

Prioritises internet traffic for better performance.

RAID

Redundant Array of Independent Disks

Improves data storage performance or redundancy.

RDP

Remote Desktop Protocol

Allows control of a computer remotely.

RMM

Remote Monitoring & Management

Used by IT providers to maintain systems offsite.

ROM

Read-Only Memory

Permanent computer memory.

RSA

Rivest–Shamir–Adleman

A popular encryption algorithm.

SaaS

Software as a Service

Software accessed via the internet (e.g. Microsoft 365).

SAN

Storage Area Network

High-speed network of storage devices.

SDN

Software-Defined Networking

Simplifies how networks are managed and configured.

SDK

Software Development Kit

Tools for developers to build applications.

SIEM

Security Info and Event Management

Centralises threat detection and alerts.

SIM

Subscriber Identity Module

Used in mobile phones to access networks.

SMTP

Simple Mail Transfer Protocol

Sends email messages.

SNMP

Simple Network Management Protocol

Manages networked devices like routers.

SoC

System on Chip

All-in-one microchip for computing tasks.

SQL

Structured Query Language

Manages and manipulates data in databases.

SSD

Solid State Drive

Fast data storage device.

SSH

Secure Shell

Secure way to access remote systems.

SSL

Secure Sockets Layer

Encrypts data between browser and server.

SSO

Single Sign-On

One login grants access to multiple systems.

TCP

Transmission Control Protocol

Ensures reliable delivery of data over the internet.

TFA

Two-Factor Authentication

Another name for MFA – double security.

TLS

Transport Layer Security

More secure successor to SSL.

TPM

Trusted Platform Module

Hardware chip for secure cryptographic operations.

UAT

User Acceptance Testing

Final phase of software testing by real users.

UDP

User Datagram Protocol

Faster, less reliable data transmission than TCP.

UI

User Interface

What users see and interact with on a computer.

URL

Uniform Resource Locator

The address of a web page.

USB

Universal Serial Bus

Common connector for data and power.

UTM

Unified Threat Management

Combines multiple security tools in one solution.

VoIP

Voice over IP

Makes phone calls over the internet.

VPN

Virtual Private Network

Secure, encrypted internet connection.

WAN

Wide Area Network

A network over a large geographic area.

WAF

Web Application Firewall

Protects web apps by filtering and monitoring HTTP traffic.

Wi-Fi

Wireless Fidelity

A wireless method for connecting to the internet.

XML

eXtensible Markup Language

A standard way to structure data for sharing.