Changing a filename can significantly impact how applications locate and interact with it. Filenames serve as primary identifiers. Many applications and systems rely on the exact filename string to find and open a specific file. If an app expects 'Report_Q1_2024.docx' but finds it renamed to 'Report_April_2024.docx', it won't automatically locate the file unless specifically updated, leading to broken links or failed operations. This differs from systems using unique internal IDs to track files regardless of name changes.

Common examples include web pages linking to image files using HTML img src="logo.jpg" tags – renaming 'logo.jpg' without updating the HTML breaks the image display. Similarly, in complex workflows like financial modeling Excel files referencing data from 'Input_Data.csv', renaming the CSV file causes spreadsheet formulas to generate errors. Operating systems like DOS historically relied heavily on specific filenames due to limitations. Modern Document Management Systems (DMS) or project management tools might break file associations and version histories if core files are renamed outside their controlled interface.

The main advantage is human readability, but a key limitation is this inherent fragility. Renaming breaks static references, potentially causing data loss or workflow disruption until links are repaired. This necessitates careful change management procedures. While some modern cloud storage or development tools (like package managers) use checksums or UUIDs to reduce dependency on filenames, manual renaming remains risky in many contexts. Future systems increasingly use internal identifiers to improve resilience against simple filename changes.