How to store variable data in a field?

Hi all,

I need to create a table to store Twitter accounts information,
Facebook and other social networks details for API login. I need to
know if it is possible to store the account details("account_details"
field) in a field that contains something like an array. I need to
store this data in an array like field because the details for each
social network accounts are different. What is my best choice for the
field "account_details"?

CREATE TABLE "account" (
"id_account" int4 NOT NULL,
"id_account_type" int4 NOT NULL,
"n_account" varchar(50) NOT NULL,
"account_details" varchar NOT NULL,
"comment" varchar(2000),
PRIMARY KEY("id_account","id_account_type")
);

I will need to store something like this:

Twitter: array("account_name" => "xpto", "hash1" => "3432454355",
"megahash" => "dfcf786fds987fds897")
Facebook: array("account_name" => "xpto", "fb_special_hash" =>
"dsdsad4535", "fb_security_hash" => "dsadsad454355",
"fb_extended_hash" => "sdasfe5r4536556fsgg")

It is possible to put something like that in a field? If yes, what
datatype should I choose? Pros and cons of doing this?

Best Regards,