I'm new to Docker and I've seen that some scrips for running containerized software require to specify either of those to match certain user and group. So I was wondering what is the difference between both? Examples below to illustrate.
Jellyfin uses UID/GID pair:
docker run -d \
--name="Jellyfin" \
--restart=always \
--network=host \
-p 8096:8096 \
-e UID=1000 \
-e GID=1000 \
-v /media:/media \
-v $HOME/docker/jellyfin/config:/config \
jellyfin/jellyfin:latest
While Calibre-web uses PUID/PGID set:
docker create --name=calibre-web --restart=always \
-v ~/books:/books \
-v /etc/localtime:/etc/localtime:ro \
-e PGID=1000 -e PUID=1000 \
-p 8081:8083 \
technosoft2000/calibre-web
While looking for info I even saw some random github repos that changed from the former to the later at some point; what's the difference between both options?