the tags page shows these when filtered for service
service × 2
web-services × 34
mapservice × 9
amazon-web-services x 1
Amazon could be deleted as it's used only once, and found easily in a search.
the 2 Service questions are both map server questions.
Web-services, the largest category overall, has a lot of map servers or services questions (4 of first 10 for example), so is mapservice meaningfully different? I think mapservice should be merged with web-service. The wms (x 49) and wfs (x34) are available if they truly need to be distinguished.