How can I snap polygons edges within the same shapefile? The objective is to get rid off blank spaces between polygons edges.
Yes, you need to use geodatabase topology if using ArcGIS.
Geodatabase topology provides an automated, rule-based solution for maintaining the spatial integrity of your GIS data.
In the topology create a rule not to allow gaps and fix the gaps. It is very fast.
Here is a video to get you started. https://www.youtube.com/watch?v=hIDxUcG8op0
Use a feature dataset inside a file geodatabase to store your data and the topology.