Abstract: A system (100) for searching and retrieving documents includes a database (106), a memory device (108), a user interface device (102) and a controller (104). The database (106) stores documents. The memory device (108) stores software, tokens and an index. The software performs methods according to a background routine (118) and a foreground routine (116). Each token (e.g., speed) has related expressions (e.g., miles per hour, mph, kilometers per hour, and kph) assigned thereto that define the token. The index has documents, having an occurrence of one of the related expressions for one of the tokens, assigned to the one of the tokens. The user interface device (102) accepts and sends search queries having a token and receives information related to the documents, having an occurrence of the related expressions for the token, responsive to a user interface process (120). The controller (104) is electrically coupled to the memory device (108), the user interface device (102) and the database (106).

Abstract: A method and an apparatus encodes and decodes blocks having a predetermined number of sectors of data bytes to detect and correct data bytes in error in each sector of a block. The method and the apparatus generates sector level check bytes for each sector in the block responsive to the data bytes in each sector according to a first level of an error correction code, and generates block level check bytes for a predetermined sector in the block responsive to the sector level check bytes of various sectors, including the predetermined sector, according to at least a second level of the error correction code.