CHECK versus a Table for an enumeration

Hi all!

I want to know what's better between these 2 solutions :

CREATE TABLE user (
...
user_type text CHECK(user_type='Root' OR user_type = 'Admin' OR
user_type = 'Standard'));

or the following :

CREATE TABLE user_type(
user_type_id integer PRIMARY KEY,
user_type_desc text);

CREATE TABLE user (
...
user_type_id integer,
CONSTRAINT user_type_exists FOREIGN KEY (user_type_id) REFERENCES
user(user_type_id));

I am really confused so I'll wait for your advices.

Thanks,

Melanie