How to add a user to PostgreSQL in Windows?

In pgadmin you can create a new “Login Role” and name it Eric and give it permissions graphically, or from command line you can do something like this

psql -U postgres -c "CREATE ROLE Eric LOGIN NOSUPERUSER INHERIT CREATEDB CREATEROLE;" mydb

see http://developer.postgresql.org/pgdocs/postgres/sql-createrole.html for information on the CREATE ROLE options.