The object of our study is a community forum on orkut that intend to bring together people interested in voluntarily learning to improve their writing in Portuguese. Our analysis addresses primarily the concepts of writing and teaching writing expressed by participants and the interactional patterns that regulate the operation of the forum, focusing on the sociointeractional roles constructed, negotiated and performed in this space. Our work is based on studies on the acquisition of writing in school and non-school contexts, developed in the field of applied linguistics (ROJO, 2003; FIAD & MAYRINK-SABINSON, 1991;MAYRINK-SABINSON, 1997); on structures of participation in social interactions in the context of schoolroom and in other spaces of presential learning, developed within the interactional sociolinguistic (PHILIPS, 2001;SHULTZ, FLORIO & ERICKSON, 1982;GOFFMAN, 2002;GARCEZ, 2006;MOITA LOPES, 1994); and studies on e-learning forums used in the context of formal and non-formal education, developed in the area of Open and Distance Learning (ODL) (PAIVA & RODRIGUES JUNIOR, 2004;OLIVEIRA & LUCENA FILHO, 2006; FUTTERLEIB & SANTOS, 1999). Inserted in the field of applied language studies, our research methodology is grounded in a qualitative interpretive analysis of data, without avoiding quantitative approaches when necessary. Our data were extracted from a corpus formed by 204 topics (or 735 posts), selected by sampling over three years and organized into four sets of 51 topics each one (Year I, Year II, Year IIIa and IIIb). Thus it encompasses a significant sample of the first three years of interactions (2006, 2007 and 2008). Based on categories developed by Dascal (2002) for the study of language as a technology, we understand the online forum as an environment, a resource and a tool at the same time. In the analyzed context, it is used for voluntary co-construction of a public space for dialogue with a view to the improvement of writing skills. This space for dialogue is also co-constructed for discussion and sharing of experiences with writing and dissemination of events, sites and other matters related to the subject. Our analysis shows that the concepts of writing and teaching writing expressed reflect or reproduce ideas deeprooted in the common sense (a good reader is a good writer, writing as gift/ inspiration) and/or traditional school concepts historically developed and disseminated (writing as a product to be corrected and evaluated, writing as a work involving planning, writing, review and adequacy to the standard form of language, writing as a set of techniques that should be learned and reproduced, guided mainly by the strategies used by major authors of the literature). In relation to the structures of participation, the open environment of the online forum seem to be innovative and to some extent promising, because besides facilitating the meeting between strangers with common interests, it enhances and streamlines the communication channels between a subject/other and a other/subject. Furthermo...