IT Mapping & Enterprise Architecture Glossary (A-Z)

IT Mapping & Enterprise Architecture Glossary (A-Z)

This glossary provides clear, concise definitions of the essential terms used in IT system mapping, enterprise architecture, and application portfolio management. It is designed for CIOs, CTOs, enterprise architects, and IT leaders who need to speak the language of architecture without wading through academic literature. Each term is defined in plain language with practical context for SMEs and mid-market organizations.

Bookmark this page as a reference. These are the terms you will encounter when mapping your information system, evaluating architecture frameworks, rationalizing your application portfolio, or communicating with consultants and vendors.

A

API (Application Programming Interface)

A defined set of rules and protocols that allows two software applications to communicate with each other. APIs are the building blocks of modern application integration, enabling data exchange and functionality sharing between systems without requiring knowledge of each system's internal workings. REST APIs and GraphQL are the most common styles in contemporary IT landscapes.

Application Inventory

A structured catalogue of every software application within an organization, including attributes such as name, vendor, version, hosting model, business owner, technical owner, cost, lifecycle status, and integrations. The application inventory is the foundational artifact of both IT mapping and application portfolio management. Without it, every other architecture activity is built on guesswork.

Application Lifecycle Management (ALM)

The governance practice of tracking each application through defined lifecycle stages -- from initial evaluation and pilot, through deployment and active use, to maintenance mode and eventual retirement. ALM ensures that applications do not linger in production indefinitely after they stop delivering value.

Application Portfolio Management (APM)

The discipline of inventorying, assessing, rationalizing, and governing the complete set of applications within an organization. APM treats the application landscape as a portfolio of investments, evaluating each application for business value, technical quality, cost, and risk. The goal is to maximize the portfolio's overall return while minimizing waste and exposure.

Application Rationalization

The process of reducing the number of applications in the portfolio by eliminating redundancies, consolidating overlapping tools, and retiring applications that no longer deliver sufficient value. Rationalization is one of the most financially impactful outcomes of application portfolio management, typically delivering 10-30% savings on application-related costs.

ArchiMate

An open, independent modeling language for enterprise architecture maintained by The Open Group. ArchiMate provides a standardized visual notation for representing the business, application, data, and technology layers of an enterprise architecture. It is frequently used alongside TOGAF and is supported by most enterprise architecture tools.

Architecture Decision Record (ADR)

A lightweight document that captures an important architectural decision, the context in which it was made, the options considered, and the rationale for the chosen option. ADRs create an institutional memory of why the architecture looks the way it does, preventing future teams from revisiting settled decisions without understanding the original reasoning.

Architecture Review Board (ARB)

A governance body that reviews significant technology decisions against architectural principles and standards. For SMEs, this does not need to be a formal committee -- a monthly meeting between the CTO, IT manager, and key stakeholders serves the same purpose. The ARB ensures that individual project decisions do not undermine the coherence of the overall IT landscape.

B

Business Architecture

The layer of enterprise architecture that describes an organization's business strategy, governance structure, key business processes, capabilities, and value streams. Business architecture provides the "why" behind every technology investment. An application only has value if it supports a business process; business architecture makes that connection explicit.

Business Capability Map

A visual representation of the complete set of capabilities an organization needs to execute its strategy, organized hierarchically. Capability maps are stable over time (capabilities change slowly, even as the processes and technologies that deliver them evolve) and provide a powerful framework for aligning IT investments with business needs.

Business Process

A sequence of activities that transforms inputs into outputs to deliver value to a customer or stakeholder. Common business processes include order-to-cash, procure-to-pay, hire-to-retire, and customer onboarding. Mapping business processes is the first step in connecting technology to business outcomes.

C

Cloud Migration

The process of moving applications, data, and infrastructure from on-premises environments to cloud platforms (IaaS, PaaS, or SaaS). Successful cloud migration requires understanding application dependencies, data flows, and infrastructure requirements -- all of which are documented through IT mapping. The most common migration strategies are the "6 Rs": Rehost, Replatform, Refactor, Repurchase, Retire, and Retain.

CMDB (Configuration Management Database)

An ITIL-aligned database that records all Configuration Items (CIs) in an IT environment -- servers, network devices, software installations, licenses -- and the relationships between them. CMDBs support operational IT service management processes (incident, change, and problem management). They are complementary to IT mapping: the CMDB provides operational granularity; the IT map provides strategic context.

Configuration Item (CI)

Any component that needs to be managed in order to deliver an IT service. CIs include hardware (servers, network devices), software (applications, operating systems), documentation, and services. Each CI is tracked in the CMDB with its attributes, relationships, and change history.

Current-State Architecture

A documented representation of the organization's enterprise architecture as it exists today. The current-state architecture is the baseline for all transformation planning. Without an accurate current state, target-state designs are disconnected from reality, and transition roadmaps are unreliable.

D

Data Architecture

The layer of enterprise architecture that defines how data is collected, stored, managed, and used across the organization. Data architecture covers data models, data flows, data storage technologies, data governance policies, and master data management. It is increasingly critical as organizations pursue data-driven strategies and face tighter data regulations.

Data Flow Diagram

A visual representation of how data moves between systems, processes, and data stores. Data flow diagrams show the source, destination, content, direction, and protocol of each data exchange. They are essential for understanding integration patterns, identifying data silos, and ensuring compliance with data protection regulations.

Data Governance

The set of policies, processes, roles, and metrics that ensure data is managed as a valued organizational asset. Data governance covers data quality, data ownership (stewardship), data access controls, data lineage, and compliance with regulations like GDPR. IT mapping supports data governance by making data flows and data ownership visible.

Data Lake

A centralized repository that stores large volumes of raw data in its native format until it is needed for analysis. Unlike data warehouses, which store structured, processed data, data lakes accept structured, semi-structured, and unstructured data. They are commonly used for big data analytics, machine learning, and exploratory analysis.

Dependency Map

A diagram that shows which components in the IT landscape depend on which other components. Dependency maps are critical for impact analysis (understanding what breaks if a specific system goes down), change management (assessing the blast radius of a modification), and retirement planning (identifying what must be migrated before a system can be decommissioned).

Digital Transformation

The strategic adoption of digital technologies to fundamentally change how an organization operates and delivers value. Digital transformation is not a technology project; it is a business strategy enabled by technology. IT mapping and enterprise architecture provide the foundation for digital transformation by ensuring that technology investments are coherent, aligned with business goals, and technically sound.

E

EAM (Enterprise Architecture Management)

The ongoing management discipline of designing, governing, and evolving an organization's enterprise architecture. EAM encompasses the processes, roles, tools, and governance mechanisms that keep architecture artifacts relevant and actionable. It is the difference between having a map and actually using it to navigate.

Enterprise Architecture (EA)

The comprehensive description of an organization's structure and operations, covering business processes, information systems, data, and technology infrastructure, and the relationships between them. Enterprise architecture provides the holistic view that enables aligned, informed decision-making about technology investments.

ESB (Enterprise Service Bus)

An integration architecture pattern that uses a centralized middleware layer to route messages between applications. ESBs were widely adopted in the 2000s and 2010s as an alternative to point-to-point integrations. While still in use, many organizations are migrating toward API-first and event-driven integration patterns.

ETL (Extract, Transform, Load)

A data integration process that extracts data from source systems, transforms it into a target format, and loads it into a destination system (typically a data warehouse or data lake). ETL processes are a common type of data flow documented in the data layer of an IT map.

F

Functional Architecture

A view of the information system organized by business functions rather than by technology. Functional architecture groups applications and services according to the business capabilities they support (e.g., finance, HR, supply chain, customer management), providing a business-oriented perspective on the IT landscape.

G

Gap Analysis

The process of comparing the current-state architecture to the target-state architecture to identify the differences (gaps) that must be addressed through projects, investments, and organizational changes. Gap analysis is a core activity in enterprise architecture planning and produces the input for transition roadmaps.

Governance (IT Governance)

The framework of policies, processes, and organizational structures that ensure IT investments support business objectives, risks are managed, and resources are used responsibly. IT governance is the management layer above enterprise architecture, ensuring that architectural decisions are made, communicated, and enforced.

H

Heat Map

A visualization technique that uses color coding to represent the status, risk, or health of components in the IT landscape. Common heat maps show application lifecycle status (green for strategic, yellow for maintain, red for retire), technical debt severity, or business criticality. Heat maps are effective communication tools for executive audiences.

Hybrid Cloud

An IT environment that combines on-premises infrastructure, private cloud, and public cloud services. Most SMEs operate hybrid environments, making IT mapping essential for understanding where workloads run, how environments are connected, and where security boundaries exist.

I

Impact Analysis

The process of determining what will be affected by a proposed change, retirement, or incident. IT mapping enables rapid impact analysis by providing visual dependency information: if application X is retired, the map shows which business processes lose support, which data flows are interrupted, and which integrations break.

Integration Pattern

A standardized approach to connecting applications and exchanging data. Common integration patterns include point-to-point connections, API gateways, message queues, ESBs, file transfers, and event-driven architectures. Documenting integration patterns is a key component of the application layer in IT mapping.

ITIL (Information Technology Infrastructure Library)

A widely adopted framework of best practices for IT service management. ITIL defines processes for incident management, change management, problem management, service level management, and other operational disciplines. The CMDB concept originates from ITIL. ITIL and enterprise architecture are complementary: ITIL governs operations; EA governs structure and evolution.

L

Landscape Map

A high-level visual representation of the entire application portfolio, typically organized by business domain or capability. Landscape maps provide a "bird's eye view" of the IT landscape and are one of the most common and useful outputs of IT mapping. They are effective for executive communication, portfolio reviews, and transformation planning.

Legacy System

An older application or infrastructure component that remains in production despite being outdated, difficult to maintain, or misaligned with current technology standards. Legacy systems are common sources of technical debt, integration complexity, and operational risk. Identifying and planning the retirement or modernization of legacy systems is a key APM activity.

M

Master Data

The core business entities that are shared across multiple applications and processes -- typically customers, products, employees, suppliers, and locations. Master data management (MDM) ensures that these entities are consistent, accurate, and governed across the organization. The data layer of an IT map documents where master data is created, stored, and consumed.

Metamodel

The model that defines the structure of the architecture model itself -- what types of objects exist (applications, processes, servers, data entities), what attributes they have, and what relationships are allowed between them. Metamodels provide consistency and rigor to architecture modeling. ArchiMate defines a standardized metamodel for enterprise architecture.

Middleware

Software that sits between applications and facilitates communication, data exchange, and integration. Middleware includes message brokers, integration platforms, API gateways, and ESBs. It is documented in the application and infrastructure layers of an IT map.

N

NIS2 (Network and Information Security Directive 2)

A European Union directive that establishes cybersecurity requirements for organizations in critical and important sectors. NIS2 requires organizations to maintain inventories of their IT assets, document network architectures, and demonstrate risk management practices. IT mapping directly supports NIS2 compliance by providing the required documentation.

O

On-Premises (On-Prem)

IT infrastructure and applications that are hosted within an organization's own physical facilities (data centers, server rooms) rather than in a cloud environment. Many SMEs operate hybrid environments with a mix of on-premises and cloud components.

P

Point-to-Point Integration

A direct connection between two applications, without middleware or an integration platform. Point-to-point integrations are simple to implement initially but create complexity at scale: an environment with N applications can have up to N*(N-1)/2 point-to-point connections. This "integration spaghetti" is a common finding during IT mapping exercises.

R

Reference Architecture

A standardized architecture template that provides guidance for building systems within a specific domain or technology area. Reference architectures accelerate design, promote consistency, and reduce risk by applying proven patterns. Organizations may define their own reference architectures or adopt industry-standard ones.

Roadmap (IT Roadmap)

A time-sequenced plan that shows how the IT landscape will evolve from its current state to the target state. IT roadmaps typically span 1-3 years and include application deployments, retirements, migrations, infrastructure changes, and integration redesigns. The roadmap connects architecture planning to project execution and budget allocation.

S

SaaS (Software as a Service)

A software delivery model where applications are hosted by the vendor and accessed by users over the internet, typically on a subscription basis. SaaS applications (CRM, ERP, HR, collaboration tools) constitute a growing share of SME application portfolios and must be included in IT mapping and APM exercises.

Shadow IT

Technology solutions adopted by business units or individual employees without the knowledge or approval of the IT department. Shadow IT creates security risks, compliance gaps, data silos, and redundant spending. IT mapping helps detect shadow IT by revealing gaps between the documented landscape and actual technology usage.

Single Point of Failure (SPOF)

A component in the IT landscape whose failure would cause a critical business process or service to stop functioning, with no redundancy or failover mechanism. Identifying SPOFs is a key objective of IT mapping and infrastructure architecture. Dependency maps and impact analysis reveal SPOFs that may not be obvious from individual system documentation.

Solution Architecture

The architecture of a specific solution or project, describing how it fits within the broader enterprise architecture. Solution architecture bridges the gap between enterprise-level planning and project-level implementation, ensuring that individual projects comply with architectural standards and contribute to the target state.

T

Target-State Architecture

A documented representation of the desired future state of the enterprise architecture, typically 2-3 years out. The target state reflects strategic business objectives translated into architectural decisions: which applications will be deployed, retired, or replaced; how data will flow; what infrastructure will host workloads. The gap between current state and target state defines the transformation roadmap.

Technical Debt

The accumulated cost of shortcuts, workarounds, and deferred maintenance in the IT landscape. Technical debt manifests as outdated software versions, unsupported operating systems, undocumented integrations, and fragile custom code. Like financial debt, technical debt accrues interest: the longer it is deferred, the more expensive it becomes to resolve. IT mapping makes technical debt visible so it can be prioritized and addressed.

TIME Model

An application portfolio classification framework that categorizes applications into four quadrants based on business value and technical quality: Tolerate (low value, high quality), Invest (high value, high quality), Migrate (high value, low quality), and Eliminate (low value, low quality). The TIME model provides a clear, actionable framework for portfolio rationalization decisions.

TOGAF (The Open Group Architecture Framework)

The most widely adopted enterprise architecture framework globally. TOGAF provides a comprehensive methodology (the Architecture Development Method, or ADM), a metamodel, and governance guidance for developing and managing enterprise architecture. While designed for large enterprises, its concepts and vocabulary are widely applicable. SMEs benefit from adopting TOGAF principles selectively rather than implementing the full framework.

Total Cost of Ownership (TCO)

The complete cost of owning and operating an application or infrastructure component over its lifecycle, including license fees, hosting costs, support contracts, customization, integration, training, and internal labor. TCO is a critical metric in APM because it reveals the true cost of applications that may appear inexpensive based on license fees alone.

Transformation Roadmap

A strategic plan that sequences the initiatives required to move from the current-state architecture to the target-state architecture. Transformation roadmaps incorporate application deployments, retirements, migrations, infrastructure changes, data initiatives, and organizational changes, with timelines, budgets, dependencies, and accountable owners.

U

Urbanization (IT Urbanization)

A methodology borrowed from city planning that applies zoning, infrastructure design, and coordinated development principles to the information system. IT urbanization divides the IT landscape into zones (business domains), districts (functional areas), and blocks (application groups), with defined rules for what can be built where and how components interact. It is widely practiced in French-speaking markets and closely related to enterprise architecture.

V

Value Stream

A sequence of activities that an organization performs to deliver a product or service to a customer, from initial request to final delivery. Value stream mapping connects business activities to the technology that supports them, providing a business-outcome-oriented view of the IT landscape.

Viewpoint

A specific perspective on the enterprise architecture, defined by the stakeholder audience and the concerns it addresses. Different viewpoints show different subsets and representations of the same underlying architecture model. For example, a CIO viewpoint might show application portfolio health and investment priorities, while a security viewpoint shows data flows and access controls. ArchiMate defines a catalog of standard viewpoints.

Z

Zachman Framework

A classification schema for organizing enterprise architecture artifacts along two dimensions: stakeholder perspective (planner, owner, designer, builder, integrator, user) and interrogative (what, how, where, who, when, why). The Zachman Framework does not prescribe a methodology; it provides a taxonomy for ensuring comprehensive coverage of architecture concerns.

Zone (Architecture Zone)

In IT urbanization, a zone is a high-level division of the information system corresponding to a major business domain (e.g., finance, operations, customer management, HR). Zones contain districts and blocks, creating a hierarchical structure that organizes the IT landscape into manageable, governable units.

Using This Glossary

This glossary covers the core vocabulary of IT mapping and enterprise architecture. As you build your organization's IT map, you will encounter these terms in frameworks, tool documentation, consultant recommendations, and industry publicationsacy.

Understanding the language is the first step toward mastering the discipline. The second step is putting it into practice.

UrbaHive provides a collaborative, visual IT mapping platform that makes enterprise architecture accessible to SMEs -- no glossary memorization required. [Start your free trial](https://www.urbahive.com) and begin mapping your IT landscape today.