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                                   EXHIBIT A

                 RELEVANT SUBSIDIARIES OF PARENT HOLDING COMPANY

PART A: TCW ENTITIES

PARENT HOLDING COMPANY:

       The TCW Group, Inc.

       Robert Day (an individual who may be deemed to control The TCW Group,
       Inc.)


RELEVANT SUBSIDIARIES THAT ARE PERSONS DESCRIBED IN RULE 13D-1(B):

(i)  Trust  Company of the West, a California corporation and a bank as  defined
     in Section 3(a)(6) of the Securities Exchange Act of 1934.

(ii) TCW  Asset  Management Company, a California corporation and an  Investment
     Adviser  registered  under Section 203 of the Investment  Advisers  Act  of
     1940.

(iii)      TCW Investment Management Company, fka TCW Funds Management, Inc.,  a
     California  corporation and an Investment Adviser registered under  Section
     203 of the Investment Advisers Act of 1940.

Note:      No Common Stock of About.Com, Inc. is held directly by The TCW Group,
     Inc.  Other  than the indirect holdings of The TCW Group, Inc.,  no  Common
     Stock  of About.Com, Inc. is held directly or indirectly by Robert Day,  an
     individual who may be deemed to control The TCW Group, Inc.

PART B: NON TCW ENTITIES

PARENT HOLDING COMPANY:

        Robert Day (an individual who may be deemed to control the entities
        described below which are not subsidiaries of The TCW Group, Inc.)

RELEVANT SUBSIDIARIES THAT ARE PERSONS DESCRIBED IN RULE 13D-1(B):

        Oakmont Corporation, a California corporation and an Investment Adviser
        registered under Section 203 of the Investment Advisers Act of 1940.





                             A-1

