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                                                               EXHIBIT 10.51


                                        * CONFIDENTIAL TREATMENT REQUESTED.
                                          CONFIDENTIAL PORTION HAS BEEN FILED
                                          SEPARATELY WITH THE SECURITIES AND
                                          EXCHANGE COMMISSION.


                           MEMORANDUM OF UNDERSTANDING

Based on preliminary discussions, Infoseek Corporation ("Infoseek") with
principal offices at 2620 Augustine Drive, Suite 250, Santa Clara, CA 95054 and
IDG COMMUNICATIONS INC. ("IDG") with principal offices at ONE EXETER PLAZA,
BOSTON, MA 02116 have decided that detailed negotiations are appropriate
regarding the possible agreement between Infoseek and IDG for (a) placement of
IDG editorial content and IDG Icons within (i) certain iZones ("IDG iZones") and
certain Topics ("Topics") of the Directory ("IDG Topics") of the Infoseek Guide
Service, (ii) on certain intermediate pages ("Interim Pages") linked from the
iZones and Topics; and (b) the placement of Infoseek Guide Icons on IDG
Websites.

This Memorandum of Understanding ("MOU") covers the draft proposal of the terms
and conditions of the placement agreement, exchange of information and conduct
of such negotiations. The parties wish to avoid any misunderstandings and
disputes which might otherwise occur in the event that a comprehensive agreement
in this subject is not fully negotiated and fully executed.

The parties acknowledge that and agree that the subject matter of these
negotiation will involve numerous interrelated business and technical factors
and that, except as set forth in this MOU, neither party shall be bound to the
other for any performance, payment, license, right, or reliance with respect to
the subject matter, unless and until all material terms have been set forth in
the separate and binding agreement signed by both parties ("Comprehensive
Agreement"). All proposals, letters, agreement drafts, points of proposed or
actual agreements, "Term Sheets", memos, charts used or exchanged in the
negotiations either shall be reflected in the Comprehensive Agreement or shall
be deemed rejected, rescinded and void upon the end of negotiations. Nothing
contained in this MOU shall be deemed to limit the scope of the negotiations or
the content of the Comprehensive Agreement.

For purposes of this MOU the term "IDG Publications" means MacWorld and PCWorld,
and such other publications of IDG as mutually agreed to by the parties, each of
which shall be the basis of an iZone pursuant to the Comprehensive Agreement.

I        A.       IDG iZone Placement Terms

                  1.       Infoseek will create an IDG iZone for the Macintosh
                           and an IDG iZone for PCWorld in collaboration with
                           IDG's editorial personnel. The IDG iZone specific to
       *                   the [] shall be on [] for the term of the
       *                   Comprehensive Agreement. Such [ ] IDG iZone shall be
       *                   positioned among the [ ] iZone listings. The IDG
       *                   iZone specific to [] shall be on [] basis for
                           the term of the Comprehensive Agreement. During the 
       *                   [] term of the Comprehensive Agreement, Infoseek will
       *                   [] iZones for the following []: [] and [].

                  2.       Infoseek will place up to five (5) links, on a
                           non-exclusive basis, from such IDG iZones to Interim
                           Pages hosted by IDG on MacWorld and PCWorld WWW
                           sites, as applicable. Interim Pages shall contain
                           articles or features either extracted from the
                           applicable IDG Publications or written specifically
                           by IDG for such pages. Advertising banners sold by
                           IDG will also be displayed on Interim Pages.

                  3.       IDG will provide to Infoseek mutually agreed upon
                           graphic files for the logos and editorial content
                           which meet Infoseek's iZones standards. Infoseek and
                           IDG anticipate that such editorial content will be
       *                   updated by IDG every [ ].

                  4.       IDG will create up to five (5) Interim Pages.
                           Creation of IDG iZones for additional IDG-based
                           publications and related Interim Pages shall be
                           subject to prior mutual agreement.

                  5.       IDG will place the Infoseek Directory logo and search
                           entry box (HTML) in a prominent position on the
                           applicable IDG Publications' Websites and track the
                           number of displays of such Infoseek logo. The
                           frequency of such tracking report will be mutually
                           agreed upon by both parties.

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* CONFIDENTIAL TREATMENT REQUESTED
  FOR REDACTED PORTION

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         B.       IDG iZone Placement Financials

                  1.       During the initial six (6) month period of the
                           Comprehensive Agreement, for each IDG iZone, IDG
        *                  will receive [ ] of the Net Advertising Revenues
                           received and recognized by Infoseek from advertisers
                           for ad impressions sold specifically for such
                           applicable IDG iZones. "Net Advertising Revenues" as
                           used herein means such gross advertising revenues for
                           such ad impressions sold specifically for such IDG
                           iZones less (a) any amounts for refunds or other
                           credits, including, but not limited to, amounts
                           credited for bad debt or fraud, or for advertisement
                           for advertisement barter or other barter revenue; (b)
                           any sales-related expenses payable by Infoseek,
                           including, without limitation, internal and/or
                           external sales commissions, advertising agency fees,
                           or royalties payable to third parties; and (c) any
                           applicable sales, use, value-added or withholding
                           taxes, or export duties or similar charges required
                           to be paid or withheld by Infoseek.

                  2.       The method of payment (either cash or advertising
         *                 credit or a combination thereof) of the [ ] 
                           Net Advertising Revenues attributable to the
                           remaining six (6) month period of the Comprehensive
                           Agreement payable by Infoseek to IDG shall be
                           mutually agreed upon prior to the commencement of
                           such six (6) month period.

                  3.       Within the IDG iZones, Infoseek will provide up to
                           five (5) links to the Interim Pages pursuant to
                           Section I.A.2. above. Infoseek and IDG will share
                           advertising revenues ("IDG Revenues") for ad banners
                           sold and delivered by IDG and displayed on such
         *                 Interim Pages. Infoseek will receive [ ] of the IDG
         *                 Net Advertising Revenues and IDG will retain [ ] of
                           the IDG Net Advertising Revenues. "IDG Net
                           Advertising Revenues" as used herein means gross IDG
                           Revenues less (a) any amounts for refunds or other
                           credits, including, but not limited to, amounts
                           credited for bad debt or fraud, or for advertisement
                           for advertisement barter or other barter revenue; (b)
                           any sales-related expenses payable by IDG, including,
                           without limitation, internal and/or external sales
                           commissions, advertising agency fees, or royalties
                           payable to third parties; and (c) any applicable
                           sales, use, value-added or withholding taxes, or
                           export duties or similar charges required to be paid
                           or withheld by IDG.

II.      A.       IDG Topics Sponsorship Terms

         *        1.       Infoseek will provide IDG with [
                                                              ], and additional
                           exclusive or non-exclusive IDG Topics related to IDG
                           Publications as may be mutually agreed upon by both
                           parties (collectively "IDG Topics"), within the
                           Topics during the one (1) year term of the
         *                 Comprehensive Agreement. Such [ ], [ ], and [ ]
                           shall be positioned one (1) level below the
                           "Computers and Internet" Topic position.

                  2.       Infoseek will place applicable IDG logos within the
                           IDG Topics pages and track the number of displays of
                           such logos. The frequency of such tracking report 
                           will be mutually agreed upon by both parties. Such 
                           logos will meet Infoseek's standard specifications 
                           for height, width and file size.

                  3.       Infoseek will place up to five (5) links, on a
                           non-exclusive basis, from each of the IDG Topics to
                           Interim Pages hosted by IDG.

                  4.       IDG will provide to Infoseek mutually agreed upon
                           graphic files which meet Infoseek's standards for the
                           Topics sponsorship.

                  5.       IDG will provide to Infoseek the IDG reviews of sites
                           which meet Infoseek's standards for reviews which
                           include number of reviews per topic, frequency of
                           updates, and style guidelines.

                  6.       IDG will create up to five (5) additional Interim
                           Pages, or have the option to use the same five (5)
                           Interim Pages as described in Section I.A2. above.
                           Additional IDG Topics and related Interim Pages shall
                           be as mutually agreed upon in writing in advance by
                           both parties.

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*CONFIDENTIAL TREATMENT REQUESTED
 FOR REDACTED PORTION

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                  7.       IDG will place the Infoseek Directory logo and search
                           entry box (HTML) in a prominent position on the
                           applicable IDG Publications' Websites and track the
                           number of displays of such Infoseek logo. The
                           frequency of such tracking report will be mutually
                           agreed upon by both parties.

         B.       IDG Topics Sponsorship Financials

                  1.       During the initial six (6) month period of the
                           Comprehensive Agreement, for each IDG Topic, IDG
         *                 will receive [ ], of the Net Advertising Revenues
                           received and recognized by Infoseek from advertisers
                           for ad impressions sold specifically for the
                           applicable IDG Topic. "Net Advertising Revenues" as
                           used herein means such gross ad revenues for such ad
                           impressions sold specifically for the IDG Topic less
                           (a) any amounts for refunds or other credits,
                           including, but not limited to, amounts credited for
                           bad debt or fraud, or for advertisement for
                           advertisement barter or other barter revenue; (b) any
                           sales-related expenses payable by Infoseek,
                           including, without limitation, internal and/or
                           external sales commissions, advertising agency fees,
                           or royalties payable to third parties; and (c) any
                           applicable sales, use, value-added or withholding
                           taxes, or export duties or similar charges required
                           to be paid or withheld by Infoseek.

                  2.       The method of payment (either cash or advertising
         *                 credit or combination thereof) of the [ ] Net
                           Advertising Revenues attributable to the remaining
                           six (6) month period of the Comprehensive Agreement
                           payable by Infoseek to IDG shall be mutually agreed
                           upon prior to the commencement of such six (6) month
                           period.

                  3.       Within the IDG Topics, Infoseek will provide up to
                           five (5) links to the Interim Pages pursuant to
                           Section II A. 3. Infoseek and IDG will share
                           advertising revenues ("IDG Revenues") for ad banners
                           sold and delivered by IDG and displayed on such
                           Interim Pages. Infoseek will receive
         *                 [                    ] of the IDG Net Advertising
         *                 Revenues and IDG will retain [ ] of the IDG Net
                           Advertising Revenues. "IDG Net Advertising Revenues"
                           as used herein means gross IDG Revenues less (a) any
                           amounts for refunds or other credits, including, but
                           not limited to, amounts credited for bad debt or
                           fraud, or for advertisement for advertisement barter
                           or other barter revenue; (b) any sales-related
                           expenses payable by IDG, including, without
                           limitation, internal and/or external sales
                           commissions, advertising agency fees, or royalties
                           payable to third parties; and (c) any applicable
                           sales, use, value-added or withholding taxes, or
                           export duties or similar charges required to be paid
                           or withheld by IDG.

III.     Logo Display Balancing for IDG iZone and IDG Topics

         On a quarterly basis, Infoseek and IDG will account for the total
         quantity of their respective logos which have been displayed on their
         respective sites for both IDG iZones and IDG Topics and Infoseek
         Directory logos on IDG Publications' Websites during the previous
         quarter. The difference in the quantity of Infoseek logo displays and
         IDG logo displays will be paid to either Infoseek or IDG, as
         applicable, in the form of advertising credits which credit shall be
         applied as follows:

                  (i)      In the event Infoseek owes IDG additional logo
                           displays Infoseek will display the quantity owed as
                           ad banners;

                  (ii)     in the event IDG owes Infoseek additional logo
                           displays, IDG will display either the quantity owed
                           as ad banners or an equivalent value in print
                           advertisements.

         Rate cards for such logo displays will be based upon mutually agreed
         upon pricing, terms and conditions as set forth in the Comprehensive
         Agreement.

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*CONFIDENTIAL TREATMENT REQUESTED
 FOR REDACTED PORTION

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         Any such ad banner credits shall be applied during the then current
quarter or the quarter immediately following.

IV.      Term

         The term of the Comprehensive Agreement shall be One (1) year from the
         effective date of such Comprehensive Agreement.

V.       General

         1.       The overall performance of both parties under the
                  Comprehensive Agreement shall be reviewed by both parties
                  approximately six (6) months from the effective date of such
                  Comprehensive Agreement.

         2.       Each party shall bear its own expenses and costs with regard 
                  to all negotiations and activities relating to this MOU.

         3.       Notwithstanding any other provision of this MOU, to the extent
                  the provisions of the Infoseek Mutual Confidential Disclosure
                  Agreement dated April 22, 1996 ("CDA"), conflict with the
                  terms of this MOU, the CDA shall control. Neither party shall
                  disclose the subject matter, the purpose, or the existence of
                  this MOU without the prior written consent of the other party,
                  except as required by law and government regulations, and
                  except for disclosure on a need to know basis to its own
                  employees, and its legal, investment, financial and other
                  professional advisors.

         4.       Neither party shall make a claim against, nor be liable to,
                  the other for consequential damages, including but not limited
                  to lost profits, suffered by it because of any performance or
                  failure to perform any obligations hereunder, or for
                  termination of negotiations without a Comprehensive Agreement.
                  Nothing in this MOU obligates either party to sell or purchase
                  any item from the other party, nor to enter into any
                  Comprehensive Agreement.

         5.       No obligation, covenant, or agreement relating to this MOU
                  shall be binding until the Comprehensive Agreement is approved
                  and signed by Infoseek and IDG.

         6.       Both parties agree that this MOU is the complete and exclusive
                  statement of understanding between the parties and supersedes
                  all prior agreements, whether oral or written, with respect to
                  the subject matter hereof.

ACCEPTED AND AGREED TO:                             ACCEPTED AND AGREED TO:

IDG COMMUNICATIONS INC.                  INFOSEEK CORPORATION

By:                                      By:
   ---------------------------                -----------------------------
         Authorized Signature                     Authorized Signature

Name:  KELLY CONLIN                      Name:  Andrew E. Newton
   ---------------------------                -----------------------------
         Print                                    Print

Title:  PRESIDENT                        Title: Vice President & General Counsel
   ---------------------------                 ---------------------------------

Date:   4/18/96                          Date:  April 22, 1996
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