Merging folders involves combining the contents of two folders into a single destination location while preserving all files. It differs from simply copying and pasting because the goal is to integrate files, preventing duplicates where possible and resolving filename conflicts instead of blindly replacing existing files. Operating systems offer built-in options where you select source and target folders; the system then compares files and typically asks how to handle items with identical names.

This is frequently used to consolidate data. For example, you might merge photos from your phone onto your computer by combining folders from different backup dates. In a workplace, team members merging updated document folders onto a shared drive ensures everyone has the latest files, avoiding scattered versions. Tools like Windows File Explorer, macOS Finder, or dedicated file managers facilitate this.

The main advantage is efficient data organization and elimination of unnecessary duplicates. However, a key limitation is the risk of unintentional overwrites if filename conflicts are not resolved carefully by choosing "keep both" or properly reviewing prompts. Therefore, users should back up folders before merging. Most systems now preserve original files by default during conflict resolution, enhancing data safety.