1. A document collaborating method among multiple users, comprising following steps of: (a) for each user creating one or more types of message accounts correspondent to a username of the user, wherein each user is able to establish contacts and a collaborative group thereof; (b) allocating a document initial version number for one or more documents which the user shares with the contacts or the collaborative group, saving an initial version of the shared document and then setting a correspondent sharing permission and a correspondent sharing time limit; (c) after finishing setting the sharing permission and the sharing time limit, automatically sending notification messages to the correspondent contacts or the correspondent collaborative group for readily notifying by the message account; and regularly reminding the sharing users to notice the time limit according to the sharing time limit by the message accounts of all sharing users of the shared document; (d) when the shared document is in a document collaborating mode, locking content being edited for each sharing user; when the locked content is being edited, regularly and automatically saving content being locked for each sharing user and allowing each sharing user to manually save the document; and automatically creating an updated version of the document under the user if the automatically saving or the manually saving by the user is finished; (e) automatically unlocking the locked content once editing the locked content is finished; and (f) when a last user in the document collaborating mode goes offline, saving a last document of the last user as a latest version of the last user and then creating a new version of the document with the latest version of the last user and other latest versions of other sharing users of the document.
1. A document collaborating method among multiple users, comprising following steps of: (a) for each user creating one or more types of message accounts correspondent to a username of the user, wherein each user is able to establish contacts and a collaborative group thereof; (b) allocating a document initial version number for one or more documents which the user shares with the contacts or the collaborative group, saving an initial version of the shared document and then setting a correspondent sharing permission and a correspondent sharing time limit; (c) after finishing setting the sharing permission and the sharing time limit, automatically sending notification messages to the correspondent contacts or the correspondent collaborative group for readily notifying by the message account; and regularly reminding the sharing users to notice the time limit according to the sharing time limit by the message accounts of all sharing users of the shared document; (d) when the shared document is in a document collaborating mode, locking content being edited for each sharing user; when the locked content is being edited, regularly and automatically saving content being locked for each sharing user and allowing each sharing user to manually save the document; and automatically creating an updated version of the document under the user if the automatically saving or the manually saving by the user is finished; (e) automatically unlocking the locked content once editing the locked content is finished; and (f) when a last user in the document collaborating mode goes offline, saving a last document of the last user as a latest version of the last user and then creating a new version of the document with the latest version of the last user and other latest versions of other sharing users of the document. 9. The document collaborating method among multiple users, as recited in claim 1 , wherein the new version of the shared document is prevented from covering previous versions before the new version; and the updated version of the shared document is prevented from covering the previously updated versions.