What is the primary difference between append and merge in GIS?

The primary difference between append and merge in GIS lies in their fundamental operations regarding the handling of datasets. When using the append function, additional data is simply added to an existing target dataset. This means that the original dataset remains intact, and the new data is integrated into it to expand the overall dataset.

On the other hand, the merge function operates by combining two or more datasets into a single dataset. However, this can lead to the creation of a new output that combines the features of both datasets while maintaining their individual properties. This merging can also include features that may not overlap or share attributes, leading to a more comprehensive dataset.

This distinction is crucial for understanding how spatial data management works in GIS, especially when deciding on the appropriate method for combining datasets based on the desired outcome—whether expanding an existing dataset or creating a new one that encompasses multiple sources.