1. A file storing system, comprising at least one server and at least one client computer, both the at least one server and the at least one client computer being connected to the Internet, the system comprising: means for creating a user account or a safe by a user, the safe or the user account being used by a first user; means for encrypting a mark with an encryption algorithm as a common encryption algorithm and an encryption key as a common encryption key, and saving the encrypted mark for the first user on the at least one server; means for determining if a current encryption algorithm is the same as or compatible with the common encryption algorithm and if an encryption key is the same as the common encryption key, wherein the determining means further comprises means for decrypting the encrypted mark using the current encryption algorithm and an encryption key, presenting the resulted mark to a user on one of the client computers, and accepting a confirmation of the user or a confirmation of the client computer; means for generating a file-uploading form to be rendered on the client computer; means for uploading a file from the client computer to the safe of the first user on the at least one server; means for encrypting the file on one of the at least one server after uploading the file or encrypting the file on the client computer before uploading the file, the encryption being performed on the file by using the current encryption algorithm that has been determined to be compatible with the common encryption algorithm using the common encryption key, one user-provided encryption key, or two user-provided encryption keys; means for saving the uploaded and encrypted file along together with file-tracking information on the at least one server; means for showing on the client computer the uploaded file together with other individually encrypted files as a user safe or other files in a secure file drawer of the first user; means for showing on the client computer any files in the user safe or any files in the secure file drawer of the first user; and means for generating a file-downloading page for a file, decrypting the file on one of the at least one server before downloading the file or decrypting the file on the client computer after downloading the file, the decryption being performed by using the current encryption algorithm and the common encryption key, a single-user provided encryption key, or two user-provided encryption keys, and downloading the file to the client computer of the first user.