Note that if you do submit a PostScript or PDF file, the ACM copyright notice should appear in the space at the bottom of column one on the first page. Permission to copy without fee all or part of this material is granted provided that the copies are not made or distributed for direct commercial advantage, the ACM copyright notice and the title of the publication and its date appear, and notice is given that copying is by permission of the Association for Computing Machinery. This approach has a lot of advantages, but assumes more infrastructure than is available to the average author. Thanks for your efforts in making your work widely and permanently available. An extra word of thanks to those authors who have provided some of the suggestions and examples in these instructions, and from whom I have learnt a lot about marking up research papers.
Trademarks are the property of their owners.