8. A client device comprising: a memory device that stores instructions relating to a browser; and at least one processor configured to execute the instructions stored in the memory device to run a browser, the browser comprising an interface configured to send a request for a document to a server computer and to receive from the server computer a sub-page of the requested document generated by an adaptation engine of the server computer based on the characteristics of a specific device class, the sub-page including a to-be-encrypted element in a client device compatible language based on the characteristics of the specific device class, wherein when the to-be-encrypted element included in the sub-page comprises the entire sub-page, an encryptor encrypts the entire sub-page, and when partially encrypted content included in the sub-page comprises less than all elements of the entire sub-page, the encryptor encrypts only the partially encrypted content included in the sub-page, and further wherein the adaptation engine surrounds the to-be-encrypted element of the sub-page with a corresponding encryption tag.
8. A client device comprising: a memory device that stores instructions relating to a browser; and at least one processor configured to execute the instructions stored in the memory device to run a browser, the browser comprising an interface configured to send a request for a document to a server computer and to receive from the server computer a sub-page of the requested document generated by an adaptation engine of the server computer based on the characteristics of a specific device class, the sub-page including a to-be-encrypted element in a client device compatible language based on the characteristics of the specific device class, wherein when the to-be-encrypted element included in the sub-page comprises the entire sub-page, an encryptor encrypts the entire sub-page, and when partially encrypted content included in the sub-page comprises less than all elements of the entire sub-page, the encryptor encrypts only the partially encrypted content included in the sub-page, and further wherein the adaptation engine surrounds the to-be-encrypted element of the sub-page with a corresponding encryption tag. 9. The client device of claim 8 , further comprising: means for identifying the to-be-encrypted element in the received sub-page, and wherein the encryptor applies partial encryption to the to-be-encrypted element.