After installation of PostgreSQL it is always started when you start Windows. If you only use this database every once in a while, PostgreSQL occupies working memory. You can configure PostgreSQL to run only when you need it.
with taskmanager you can assess how many system resources PostgreSQL occupies: 5 Postgres processes times 5 Mb is about 25 Mb.
You can use PGadmin to stop the Postgres services. This helps only during your current Windows session. Each time you rebooted, Postgres will run again.
When the Postgres services are down, you cannot access the databases. You wll get an error message.
You can restart the Postgres services also from within PGadmin.
If you want to shut-down Postgres by default, and only restart it manually when you need it,
you have to configure the windows services. You can access these for instance via the run toolbix
in the Start menu.
Select the PostgreSQL service, double-click and choose the Start-up type to be Manual.
You can restart the service manually here too, but we recommmend to do this via PGadmin, and not
access the windows services too often as you may make mistakes here.