Type of bare text strings

What type are bare strings considered if they haven't been cast? I'm curious as
to how the first case is of size 5, and how the last case is 301...

decibel=# select pg_column_size('test');             5

decibel=# select pg_column_size('test'::varchar);             8

decibel=# select pg_column_size('test'::text);             8

decibel=# select pg_column_size('test'::name);            64

decibel=# select pg_column_size('test'::char(4));             8

decibel=# select
pg_column_size('123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890');
         301
 

decibel=# 
-- 
Jim C. Nasby, Sr. Engineering Consultant      jnasby@pervasive.com
Pervasive Software      http://pervasive.com    work: 512-231-6117
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