Global Location Number
The Global Location Number (GLN) is a globally unique 13-digit identifier standardized by GS1 for recognizing physical locations, legal entities, functional entities, and trading partners within supply chains and business operations.[1] It enables precise identification of diverse entities, such as warehouses, offices, departments, or entire organizations, facilitating seamless data exchange and process optimization across international transactions.[2] The GLN structure consists of three components: a GS1 Company Prefix (a variable-length identifier assigned to a company by a GS1 member organization), a Location Reference (a company-assigned code specifying the exact location or entity), and a check digit calculated using the GS1 modulo 10 algorithm to ensure data integrity.[3] This format complies with the international standard ISO/IEC 6523, which defines a framework for global identifiers, allowing the GLN to interoperate with other systems like electronic data interchange (EDI) and XML messaging.[3] GLNs are assigned through GS1 member organizations, either via a GS1 Company Prefix for multiple locations (starting at around $250 annually for up to 10 locations, depending on the region) or as individual GLNs for single-use needs (typically $30).[2] They support applications in industries like healthcare, retail, and logistics, where accurate location tracking enhances visibility, reduces errors in shipments, and streamlines compliance with regulations such as those for pharmaceutical supply chains.[4] For instance, in healthcare, GLNs link locations to associated data like addresses and trade classes, improving inventory management and recall processes.[4] Beyond physical sites, GLNs can identify digital or virtual locations, such as email addresses or websites, providing flexibility for modern e-commerce and automated trading.[1] Verified by GS1 services, these numbers build trust among partners by confirming the legitimacy of the identified entities, ultimately contributing to efficient global commerce.[5]Overview
Definition and Purpose
The Global Location Number (GLN) is a 13-digit GS1 Identification Key designed to uniquely identify physical locations, such as warehouses and stores; functional or operational locations, such as loading docks and departments; and legal entities, such as companies and divisions.[3] This identifier serves as a standardized "electronic address" within the GS1 system, enabling precise recognition of parties and places across global supply chains.[6] The primary purpose of the GLN is to provide unambiguous identification that fosters trust, efficiency, and seamless data sharing in business transactions and electronic commerce.[3] By assigning GLNs, organizations can verify the authenticity of locations and entities through services like "Verified by GS1," which confirms compliance with GS1 standards.[5] Key benefits include its global uniqueness, which eliminates confusion in international operations; flexibility to denote any level of location from entire buildings to specific rooms; and integration with GS1 systems such as the Global Data Synchronization Network (GDSN) for accessing synchronized master data.[6] These attributes support applications in electronic data interchange (EDI) and global trade by reducing errors and streamlining processes.[3] The GLN is recognized by international standards bodies, including the United Nations Centre for Trade Facilitation and Electronic Business (UN/CEFACT) and the International Organization for Standardization (ISO) under ISO/IEC 6523 with the International Code Designator (ICD) 0088.[3] It is supported by the GS1 network in 116 countries as of 2023 and used by more than 1 million companies worldwide across various industries as of 2023, demonstrating its broad adoption for multi-sectoral supply chain management.[7][8]Historical Development
The origins of the Global Location Number (GLN) trace back to the establishment of the GS1 standards system in the 1970s, which began with the development of the barcode by U.S. grocery industry leaders in 1973 and the first commercial scan in 1974 under the Uniform Code Council (UCC).[7] This foundational infrastructure for product identification laid the groundwork for broader supply chain standards, including the need for standardized location identifiers to support emerging electronic data interchange (EDI) processes in the 1980s and 1990s. During this period, UCC and the European Article Numbering Association (EAN) developed location codes to facilitate global trade and EDI messaging, addressing the limitations of proprietary internal codes that hindered cross-border interoperability among trading partners.[7] By 1989, the first GS1 EDI standard was published, incorporating these location codes to enable efficient communication of party and site details in business transactions.[7] The formalization of the GLN occurred in the early 2000s amid efforts to unify international standards, culminating in the 2005 merger of UCC and EAN to form GS1, a single global organization with 101 member organizations.[7] This unification standardized location identification under the GLN name, building on prior UCC/EAN codes to create a 13-digit key for uniquely identifying physical locations, legal entities, and functional roles worldwide. In the mid-2000s, GLN integration advanced with the formation of EPCglobal in 2003, which extended GS1 standards to radio-frequency identification (RFID) technologies, enabling serialized location data for enhanced supply chain tracking.[7] Subsequent milestones refined GLN usage, including the introduction of formal allocation rules to ensure consistent assignment and management across industries.[9] The 2010s saw enhancements in the GS1 General Specifications for RFID compatibility and digital verification, supporting automated data capture and validation.[10] Further developments included the launch of the GS1 Registry Platform in 2019 for managing GLNs and GTINs, and the GS1 Digital Link standard in 2020, which integrates GLNs with QR codes for enhanced digital connectivity. In 2023–2024, GS1 celebrated the 50th anniversary of the barcode, highlighting the GLN's evolution as a cornerstone of interoperable identification since the barcode's inception.[11] These advancements, including post-COVID efforts to bolster supply chain resilience, continue to emphasize the GLN's role in global trade networks.[12]Structure
Composition of the GLN
The Global Location Number (GLN) is a 13-digit numeric identifier designed for global uniqueness in identifying physical locations, legal entities, or functional entities. It consists of three main components: the GS1 Company Prefix, the Location Reference, and the Check Digit. The first 12 digits are formed by the GS1 Company Prefix and the Location Reference combined, with the final digit serving as the Check Digit for error detection.[3][6] The GS1 Company Prefix is the initial portion of the GLN, ranging from 6 to 10 digits in length, and is uniquely assigned by a GS1 Member Organization to a subscribing company or organization. This prefix ensures global uniqueness by linking the identifier to the issuing GS1 authority and the specific subscriber, preventing overlaps across different regions or entities. The length of the prefix determines the number of digits available for the subsequent component, with shorter prefixes allowing more flexibility for detailed location coding. For instance, a 6-digit prefix provides up to 1,000,000 possible location references, suitable for very large organizations with extensive sites.[3][6] The Location Reference follows the GS1 Company Prefix and has a variable length of 2 to 6 digits, filling the remaining space to reach exactly 12 digits in total for these two components. This part is assigned internally by the company holding the prefix to denote a specific location, such as a warehouse, office, or even a sub-location like a department floor within a building. It enables hierarchical structuring, where companies can encode parent-child relationships (e.g., a main facility as the parent and its divisions as children) without embedding geographic data directly into the number. The GLN contains no alphabetic characters, relying solely on numeric digits for simplicity and compatibility with barcode and data interchange standards.[3][6] To illustrate, consider a company with a 7-digit GS1 Company Prefix of 1234567 and a 5-digit Location Reference of 89012 for one of its warehouses; these combine to form the base number 123456789012. A different location under the same company might use 123456700001 for its headquarters. The full 13-digit GLN is completed by appending the Check Digit to this base. This modular composition allows companies to manage thousands of locations efficiently while maintaining a fixed overall length.[6]| Prefix Length | Location Reference Length | Maximum Locations per Prefix |
|---|---|---|
| 6 digits | 6 digits | 1,000,000 |
| 7 digits | 5 digits | 100,000 |
| 8 digits | 4 digits | 10,000 |
| 9 digits | 3 digits | 1,000 |
| 10 digits | 2 digits | 100 |
Check Digit Calculation
The check digit is the thirteenth and final digit of a Global Location Number (GLN), computed using a modulo 10 algorithm applied to the preceding 12 digits, which comprise the GS1 company prefix and location reference.[13] This method, standardized by GS1, employs alternating weights of 1 and 3 to the digits, ensuring the overall GLN validates correctly when scanned or entered, thereby verifying data integrity. It is the same calculation used for all fixed-length GS1 identification keys, such as GTINs and SSCCs, promoting consistency in error detection across supply chain systems.[13] The algorithm follows these steps: First, take the 12-digit input (GS1 prefix plus location reference). Second, assign weights by multiplying alternate digits by 3, beginning with the rightmost digit (the 12th position); the remaining digits receive a weight of 1. This is equivalent to weighting even-numbered positions by 3 and odd-numbered positions by 1 when counting from the left (position 1 as the leftmost digit). Third, compute the sum of these weighted values. Fourth, find the remainder when this sum is divided by 10. Finally, the check digit is 0 if the remainder is 0, or 10 minus the remainder otherwise.[13][14] Mathematically, for digits d_1 to d_{12} (with d_1 as the leftmost), the weighted sum S is given by: S = d_1 + 3d_2 + d_3 + 3d_4 + d_5 + 3d_6 + d_7 + 3d_8 + d_9 + 3d_{10} + d_{11} + 3d_{12} The check digit c is then: c = (10 - (S \mod 10)) \mod 10 This ensures the total weighted sum of all 13 digits (including c weighted by 1 in the rightmost position) is congruent to 0 modulo 10. For example, consider the 12-digit input "123456789012". The weighted values are: $1 \times 1 = 1, $2 \times 3 = 6, $3 \times 1 = 3, $4 \times 3 = 12, $5 \times 1 = 5, $6 \times 3 = 18, $7 \times 1 = 7, $8 \times 3 = 24, $9 \times 1 = 9, $0 \times 3 = 0, $1 \times 1 = 1, $2 \times 3 = 6. The sum S = 92, $92 \mod 10 = 2, so c = 10 - 2 = 8. The complete GLN is thus "1234567890128".[13] The primary purpose of this check digit is to detect common transcription errors, such as single-digit mistakes or adjacent transpositions, with a detection rate exceeding 90% for such faults in practice. By appending this calculated value, the GLN gains built-in validation without requiring additional computational overhead during routine use.[14]Allocation and Management
Obtaining and Assigning GLNs
To obtain a Global Location Number (GLN), companies must acquire a GS1 Company Prefix from their local GS1 member organization, which grants the right to generate unique identifiers for locations and parties within their operations.[1] This process begins with business verification, where the applicant provides company details such as name, address, and contact information to confirm legitimacy.[2] For example, in the United States, organizations can purchase a GS1 Company Prefix through the GS1 US online store by selecting the desired capacity (e.g., for 1-10 locations at an initial fee of $250, with an annual renewal of $50), completing the payment, and receiving the prefix via email or certificate.[15] Alternatively, a single GLN can be obtained directly for a one-time fee of $30 without a prefix, suitable for entities needing only one identifier, such as certain pharmaceutical dispensers that may already hold a pre-assigned GLN.[16] Worldwide, over 110 GS1 member organizations facilitate this in more than 100 countries, with GS1 US serving over 300,000 members across 25 industries.[17][18] Once the GS1 Company Prefix is secured, internal assignment of GLNs occurs within the company by creating a Location Reference—a unique code for each site, such as a warehouse, office, or department—appended to the prefix to form the 12-digit base number.[2] For instance, a company might assign one GLN per physical location like a distribution center or even per functional area within a building to support precise supply chain tracking.[6] The company then calculates the 13th check digit using the GS1 Check Digit Calculator to ensure data integrity, following the standard modulo-10 algorithm applied to the preceding digits.[19] There is no limit on the number of sub-locations or GLNs that can be generated under a single prefix, provided it aligns with the prefix's allocated capacity (e.g., a shorter prefix allows for more combinations).[20] Assigned GLNs may be registered voluntarily in GS1's global lookup systems, such as Verified by GS1, for verification by trading partners, though this is not mandatory for basic use.[5] Requirements for obtaining and maintaining a prefix include annual renewal to keep the identifiers active, with fees scaled by capacity (e.g., $500 annually for up to 1,000 locations in the US).[2] Businesses must adhere to GS1's allocation rules to avoid duplication, but non-profits in select regions may qualify for reduced or waived fees through their local member organization.[17] This structured approach ensures GLNs remain globally unique and scalable for diverse operations.Governance and Standards
The governance of the Global Location Number (GLN) is overseen by GS1, a neutral, not-for-profit international standards organization headquartered in Brussels, with 116 member organizations operating in 120 countries.[17] Founded in 1973 through the establishment of the Uniform Product Code Council in the United States—which later evolved into the Uniform Code Council and merged to form the global GS1 entity—GS1 develops and maintains the rules for GLN assignment and usage to ensure interoperability in global supply chains. The GS1 Global Office sets the core standards through documents such as the GS1 General Specifications (latest release 25.0) and the GS1 GLN Allocation Rules Standard (release 3.0.2, ratified August 2022), which outline principles for consistent GLN management.[17][21][9] Local enforcement is handled by GS1 Member Organizations, which issue company prefixes and support companies in applying the rules regionally while adhering to global guidelines. This structure enables GS1 to facilitate 10 billion daily transactions worldwide across diverse industries.[3][17] Compliance with GLN standards emphasizes mandatory uniqueness, requiring each GLN to be globally distinct to avoid duplication in business transactions. The allocation rules provide guidelines for hierarchical assignment, such as designating parent-child relationships for locations within an organization—for instance, a corporate headquarters as a parent GLN and individual warehouses as child GLNs—to support structured identification without overlap. To verify authenticity and adherence, GS1 offers the "Verified by GS1" service, which allows users to check the validity of GLNs and associated data through a centralized registry, including enhancements for digital verification introduced in updates around 2021-2022 to improve data trust and accessibility.[22][5][23] These measures ensure that GLNs meet quality benchmarks, with audits conducted via the GS1 system to confirm proper allocation and usage.[1] On the international front, the GLN aligns with ISO/IEC 6523 for structured identification codes, specifically using International Code Designator (ICD) 0088 to denote GLNs in electronic messaging and data exchange. This alignment promotes seamless integration in global systems. Additionally, the United Nations Centre for Trade Facilitation and Electronic Business (UN/CEFACT) recognizes and endorses GLNs for use in trade documents and electronic business processes, facilitating cross-border compliance and reducing administrative barriers in international commerce.[24][25][3]Applications
Supply Chain and Logistics
In supply chain and logistics, the Global Location Number (GLN) primarily serves to identify ship-to and ship-from locations on logistic labels, enabling automated processing of goods movement.[3] It is encoded in GS1-128 barcodes as part of the GS1 Logistic Label, which supports scanning for cross-docking operations and inventory management at warehouses and distribution centers.[3] This standardization allows for seamless identification of physical locations such as loading docks or storage areas, reducing manual interventions in routing and handling.[26] A key example of GLN application is encoding it on pallets to facilitate warehouse routing, where the number directs goods to specific destinations within multi-tier supply chains.[26] GLNs integrate with Electronic Product Code Information Services (EPCIS) to provide real-time visibility of shipment locations, capturing events like loading and unloading across global networks.[27] Additionally, in the Global Data Synchronization Network (GDSN), GLNs enable partner data synchronization by uniquely identifying trading locations, ensuring accurate exchange of master data for logistics planning.[6] The use of GLNs yields significant benefits, including reduced errors in deliveries through standardized location identification and enhanced efficiency in supply chain operations.[3] Studies by GS1 indicate that implementing GLNs in logistic processes can streamline data exchange, supporting faster processing and greater visibility in complex, multi-tier networks.[3] In practice, GLNs are applied in retail for store-level identification during replenishment, in logistics for carrier manifests to track consignments, and in finance for specifying invoice-related locations to automate billing reconciliation.[1]Healthcare and Other Sectors
In healthcare, the Global Location Number (GLN) serves as a standardized identifier for facilities, functional entities, and physical locations, enabling precise tracking and management of medical supplies and equipment. Hospitals, pharmacies, and specific device storage areas are assigned unique GLNs to facilitate interoperability across the supply chain, as outlined in the GS1 Healthcare GLN Implementation Guideline.[28] This supports the traceability of pharmaceuticals and medical devices from manufacturer to point of care, aligning with regulatory requirements such as the U.S. Food and Drug Administration's Drug Supply Chain Security Act (DSCSA), which mandates unique identification for trading partners and locations to prevent counterfeit drugs and ensure patient safety. For instance, GLNs are applied to shipping labels in sterile environments, such as operating rooms or central supply departments, to maintain inventory accuracy and reduce handling errors during transport. Sub-location GLNs further enhance granularity within healthcare settings, allowing identification of specific areas like hospital wings, nursing stations, or individual treatment rooms, which improves operational efficiency and supports electronic data interchange for ordering and invoicing. The Association for Healthcare Resource & Materials Management (AHRMM) emphasizes that GLNs tied to associated names, addresses, and classes of trade contribute to better supply chain visibility, ultimately aiding in cost reduction and enhanced patient outcomes by standardizing location data across providers and suppliers.[4] Beyond healthcare, GLNs are applied in diverse sectors to identify entities and locations for operational and traceability purposes. In finance, GLNs function as unique identifiers for legal entities and trading parties in electronic invoicing and payment systems, ensuring accurate transmission and reconciliation of transactions under standards like those for e-invoicing. In manufacturing, GLNs enable identification of plant-floor operations, such as specific production lines or assembly areas, providing flexibility to track assets and workflows at granular levels within facilities. For produce traceability, the Produce Traceability Initiative (PTI) guidelines recommend GLNs for farms, packing sheds, and loads to capture critical tracking events, including lot codes and transformations, thereby supporting compliance with food safety regulations like the FDA's FSMA Rule 204, with full compliance originally set for January 20, 2026, but proposed to be extended to July 20, 2028, as of August 2025.[29][30] These applications extend GLN usage to over 25 industries, including automotive for parts distribution and consumer goods for retail inventory management, demonstrating its versatility in global business communications.[6]Encoding and Representation
In Barcodes and Labels
The Global Location Number (GLN) is primarily encoded in linear barcodes using the GS1-128 symbology, which employs Application Identifiers (AIs) to specify the data's meaning and structure. The most common AI for GLN in logistics is 410, indicating the "Ship to - Deliver to" location, followed directly by the 13-digit GLN without separators. This format enables automated scanning for routing shipments to specific destinations, such as warehouses or facilities. Another relevant AI is 412 for "Purchased from" locations, which identifies the originating site or supplier in the supply chain.[10][31] In GS1 Logistic Unit Labels, GLNs are integrated as part of standardized labels applied to pallets, containers, or other shipping units identified by Serial Shipping Container Codes (SSCCs). These labels typically position the GLN barcode adjacent to the SSCC barcode, with human-readable interpretations (HRI) printed below each barcode in uppercase text (e.g., "SHIP TO LOC" followed by the GLN digits). The HRI must be at least 3 mm high for readability, ensuring manual verification alongside automated scanning. For scannability, GS1-128 barcodes require a minimum X-dimension of 0.495 mm, a symbol height of 31.75 mm, and quiet zones of at least 10 times the X-dimension on all sides to prevent interference from adjacent elements.[31][10] For radio-frequency identification (RFID), GLNs are embedded in Electronic Product Code (EPC) tags using the Serialized Global Location Number (SGLN) encoding scheme, which extends the base GLN with optional identifiers for sub-locations (e.g., via AI 254). This allows RFID readers to capture precise location data during transit, linking it to associated items or assets without relying on visual barcodes. SGLN supports both 96-bit and 195-bit formats in Gen 2 RFID tags, with binary encoding partitioned by company prefix length for efficient memory use.[32] These representations adhere to the GS1 Logistic Label Guideline (Release 1.3) and GS1 General Specifications (Release 25.0, January 2025), which define symbology requirements, placement guidelines (e.g., 400-800 mm from the pallet base in picket-fence orientation), and verification procedures to ensure 99.5%+ decode rates in logistics environments. For instance, a barcode encoded as (410)1234567890128 would route a pallet directly to the specified delivery location, with the check digit validating accuracy during scans.[31][10]In Electronic Data Interchange
The Global Location Number (GLN) serves as a core identifier in Electronic Data Interchange (EDI) systems, enabling the unique recognition of parties and locations within automated business transactions. In the UN/EDIFACT standard, GLNs are primarily transmitted in the NAD (Name and Address) segment to specify entities such as buyers, sellers, or despatch parties. For instance, in messages like DESADV (Despatch Advice Message) or INVOIC (Invoice Message), a buyer location might be denoted as NAD+BY+5412345000013::9, where the qualifier ::9 indicates the use of a GLN for identification. This integration ensures unambiguous routing and processing of data in supply chain communications, reducing errors in machine-to-machine exchanges.[33] Within the GS1 eCom framework, which standardizes EDI for electronic business messaging, the GLN is essential for facilitating B2B interactions across global supply chains. It supports the core identification of trading partners in various message types, promoting seamless data flow without reliance on textual addresses. Additionally, GLNs are integral to the Global Data Synchronization Network (GDSN), where they are required for certified data pools to synchronize product master data among trading partners, ensuring consistency in shared attributes like location details. In EPCIS (EPC Information Services) events, GLNs identify locations involved in tracking events, such as object observations during shipment, enhancing visibility in real-time supply chain monitoring.[3][6][34] In digital formats beyond traditional EDI, GLNs are represented as pure 13-digit numeric values in structured data exchanges like XML or JSON, for example,Comparisons
Similarities to Other GS1 Identifiers
The Global Location Number (GLN) shares fundamental structural elements with other GS1 identification keys, such as the Global Trade Item Number (GTIN) and Serial Shipping Container Code (SSCC). All are composed using a GS1 Company Prefix allocated to member organizations, followed by a location- or item-specific reference, and conclude with a single check digit calculated via the same modulo-10 algorithm to ensure data integrity during transmission.[38][39] While the GLN is fixed at 13 digits and the GTIN varies (8, 12, 13, or 14 digits), the SSCC extends to 18 digits with a leading extension digit, but all maintain the core principle of prefix-based composition for consistent encoding.[40][39] As part of the broader GS1 ID Keys framework, the GLN integrates seamlessly with GTIN, SSCC, and others to facilitate interoperability across global supply chains. These keys enable standardized data capture and exchange through shared technologies, including barcodes via the GS1-128 symbology, RFID tags using Electronic Product Code (EPC) standards, and Electronic Data Interchange (EDI) formats.[38][40] For instance, all support encoding in linear barcodes and RFID for real-time identification of locations, items, or logistics units, promoting efficient tracking and automation.[39] The uniqueness of the GLN mirrors that of other GS1 keys, achieved through centralized allocation of the GS1 Company Prefix by GS1 member organizations worldwide, ensuring no duplication across borders or industries. This prefix system underpins global resolvability, allowing each key to reference authoritative master data in the Global Data Synchronization Network (GDSN).[38][40] Like the GLN, both GTIN and SSCC utilize Application Identifier (AI) prefixes in data carriers—such as AI 01 for GTIN—to denote their type and format during scanning or transmission.[39][38] These shared traits trace back to the evolutionary roots of GS1 keys in the merged EAN and Uniform Code Council (UCC) systems, which standardized numbering for international trade in the late 20th century before GS1's formation in 2005.[40][39] This common heritage ensures that GLN, GTIN, and SSCC function as complementary components within the GS1 ecosystem, supporting end-to-end visibility without proprietary barriers.[38]Differences from Other GS1 Identifiers
The Global Location Number (GLN) differs from the Global Trade Item Number (GTIN) primarily in purpose and scope: while the GTIN identifies trade items such as products or services for use in point-of-sale scanning, ordering, and invoicing, the GLN uniquely identifies physical locations, legal entities, or functional roles within the supply chain, such as warehouses, ship-to addresses, or business parties, without any linkage to specific products. Structurally, GTINs vary in length (8, 12, 13, or 14 digits, often padded to 14 with an indicator digit for certain applications), whereas GLNs are strictly 13 digits, comprising a GS1 Company Prefix, a Location Reference, and a check digit, emphasizing location-specific identification over item variability. In contrast to the Serial Shipping Container Code (SSCC), which identifies dynamic logistic units like pallets or containers for tracking shipments through the supply chain, the GLN is designed for static or semi-static entities such as sites or organizations, lacking the serial reference component that enables unique tracking of individual transport units. The SSCC is an 18-digit number incorporating an extension digit, serial reference, and check digit to handle transient logistics movements, while the GLN's 13-digit format supports ongoing party verification and routing without serial elements, avoiding duplication in internal systems unlike ad-hoc SKUs.[41] Compared to the Global Returnable Asset Identifier (GRAI), the GLN focuses on parties and locations rather than individual returnable assets like containers or totes, which the GRAI tracks through asset management processes with a functional serial number for reusability. Although both can extend beyond 14 digits (GRAI minimally 14 digits with an asset type and serial, prefixed by AI 8008), the GLN uses AIs like 410 or 414 for location roles and maintains flexibility for legal or physical distinctions without product or asset-specific linkages, often paired with GTINs on labels to denote a product at a specific location while functioning standalone for entity verification.| Identifier | Purpose | Length | Key Structural Distinction |
|---|---|---|---|
| GLN | Locations, entities, functions | 13 digits | GS1 Prefix + Location Reference + Check Digit; no serial or asset type |
| GTIN | Trade items (products/services) | 8-14 digits | Variable, often with indicator digit; item-focused |
| SSCC | Logistic units (shipments) | 18 digits | Extension Digit + Serial Reference + Check Digit; dynamic tracking |
| GRAI | Returnable assets | ≥14 digits (up to 30 chars) | Asset Type + Serial + Check Digit (AI 8008); reusability emphasis |