by Gautam Shah ➔

Library -Alexandria

A document is a self sufficient or a unique collection of specific information or structured data, which can be stored, retrieved or communicated. Any such lot, when referred to, provides the intended information.

Hamurabi Documents

Documents have many different formats depending on what they carry, and how these are to be stored, retrieved or communicated. Traditional documents, in written, pictorial or graphical form, are the most common units of communication.


Paperwork Bureaucracy Work Aktenordner Office

A document serves many different purposes, it describes, defines, specifies, reports or certifies activities, lists the requirements for performing activities or mentions results of activities.


Letters, reports drawings, specifications, procedures, instructions, records, radio-graphs, computer tapes and disks, purchase orders, invoices, process control charts, films, microfilms, photograph etc., are all examples of documents.

Document storage system

When information manifests as data, a document comes into being. A document carries many identifiers such as:

  • time (of origin)
  • size (of storage, transmission time & effort)
  • content
  • place of origin
  • place of a destination
  • affiliations
  • embedded codes
  • signs, symbols
  • language
  • style
  • mode of communication
  • extent of exposure
  • limits and conditions of relevance
  • It is through these type of identities that a document begins to be relevant or worthy of access.


In modern terminology, information lots or documents are called Files, because it helps in identifying the contents. A filed information or data lot has: a title, a list of contents, description of contents and the mass of contents. Additionally it occupies a space, so size and the birth context (date/ time/ location/ other circumstances of origin). Beyond these primary endowments, a file may be given many levels of attachments (references).

Disc Storage

A Simple data file may contain several sub entities, each of which may be allocated a specific physical space. A complex file may have varied or standard size of pre-set space allocations. Alternatively a Start and/or End marker (fixed or floating) may separate file partitions. Filters decide which of the entities are to be allocated a free or variable space. Data entities are invariably accompanied by their titles or identifiers.

Neural Network


Data entities in a file remain static or are changeable. Conditions that cause a data to remain static or be variable could be external or are internal. The internal conditioners, titles and filters are inseparable parts of information files. In Static files, the structure remains unaltered even while data entities are changed. The meaning deriving out of the file, however, may change. In Dynamic files the structure of the file gets altered along with the change in data entities. Static files are easy to process, but cannot provide qualitative information. Static files usually contain data that is mathematical or substantially logical. Dynamic files are difficult to process and provide little quantitative information. Dynamic files contain data that is generally textual or metaphoric.



Post -by Gautam Shah


Traditional street side grinding of knives and scissors


Metal abrading grinder

The first abrading tools were rough stones and hard grained abrasive sands. Tough fibres like asbestos, wool, and coir were also used for buffing purposes. Today sandpapers in sheet, stripes and tape forms are available with paper and cloth backing and bonded with water-based gums and synthetic resins. Carborundum and other man-made ceramic granules are embedded or cast in various base materials and shaped as discs, wheels, cones, rings, etc. for use with various machines. Such abrading tools are also used for drilling, edge dressing, tunneling, boring, etc.


Abrading stones are used to grind, de-husk and surface polish the food grains, nuts and seeds. This is done by pounding or by milling between stones. Nails, Screws, Nut-bolts, Toffees and sugar coated pills are rotated in drums to polish the surface.


Automobile and other lacquer finishes are buff-polished with very fine abrading media mixed with wax and silicon oil-based rubbing compounds. Abrading materials are also included in soft articles used in household utensil cleansers and jewellers polish to the hardest known material, the diamond. Leather, Jute, Linen, Chamois and may other materials with harder fibers are used for rubbing and polishing. Abrasives are used in the form of tumbling and vibratory mass-finishing media as for polishing for nails, sandblasting, flour mill stones, ball mills. Spectacle lenses and telescope lenses are ground with a abrading and then polishing media.

Hubble Telescope lens grinding

Abrasive materials and tools can cut through hardest materials at a faster speed than metal saws, while generating less heat and providing smoother cut face. New hard alloys and ceramics can only be cut by abrasives. Granite, marble, slate, and highly vitrified tiles are cut to size with diamond abrasive wheels. Grooves for expansion joints in runways and roads, holes in RCC structures are made by metal blades with embedded diamond abrasives. Metal components are cleaned by grinding tools of wire or hair wheels or by sand blasting.

Files of Different grains


FILES: Files are abrading tools. Files are of many different cross sections, lengths, notch configurations and the coarseness of the cut (density -teeth per area). A file could be very thin, almost like a knife with a serrated cutting edge, to a wide chequered figured plate. The most common sections are rectangular, triangular, round and half round. Most files have reduced size of section at their tail end. There are three tooth forms: The single-cut file has rows of parallel teeth that cut diagonally across the working surfaces. The double-cut file has rows of teeth crossing each other. Rasp teeth are disconnected round top notches. Rasp files, or rasps, are usually very coarse and are used primarily on wood and also soft materials like leather, aluminium, lead, etc. Files are used for many different purposes: to smoothen nails, cut injection vials of glass, removing human skin blemishes and birthmarks, for shaping bones during plastic surgery, removing spots and discolourations from suede fabrics, and for levelling teeth.

Grinder brush of Metal or Hair

Milling Machine Control Joinery Industry Carpenter