Indexing – Meaning, Objectives, Essentials, Types, Advantages & Disadvantages

What is Indexing?

Indexing office files
Indexing office files – Meaning, Objectives, Essentials, Types, Advantages & Disadvantages

Indexing performs an indispensable service to the filing function. Index, is a reference list used for locating a particular document in the filing equipment. Similarly, while filing a document, the index aids the records clerk in tracing out the place where the particular paper should be filed. Particularly when a large number of files are maintained for various purposes, index is very essential. Index is anything that indicates or points out.

According to J.C. Denyer.

the primary function of index is to act as a guide to a body of data or to a collection of records.

Since the term index is in popular usage, we need not elaborate the meaning of the term further.

Indexing and Classification

The term indexing should not be confused with the term “Classification”. Classification of filing means a method of filing while indexing, on the other hand, means the method used for making reference to the records filed.

Moreover, if the files are arranged alphabetically, chronologically or geographically in alphabetical order, there is no need for having a separate index as the order of the files is already known.The order of the files itself is self-index.

On the other hand, if no such arrangement is followed, a separate index must be maintained giving file titles in some order. In some offices, a separate index is kept even if the files are arranged on self-indexing system. However, such indexes are more elaborate and contain various types of information.

Objectives of Indexing

The principal objective of indexing is to ensure that filed papers are located easily and quickly whenever they are needed. Therefore, indexing adds to the efficiency of the filing method. It ensures speed in finding the files and consequently results in savings in time, labour and the resultant economy. This object can be best achieved where the right type of indexing system is chosen.

Though a separate index is not necessary when files are maintained in alphabetical classification, it is essential in other, systems of classification.

Essentials of a Good Index System

In order to achieve these objectives, a good system of indexing should have the following features:

1. The Index system should be simple and easy to understand.

2. It should be economical in operation.

3. It should allow for speed.

4. It should go well with the system of filing in the organization.

5. It should be flexible to allow for expansion whenever needed.

Advantages of a Good Indexing System

A good system of indexing i.e. which goes well with the filing methods provides the following benefits.

1. Easy Location

The required papers and documents can be easily located. No extra time is needed. Hence, referencing shall not be a painful process.

2. Easy Cross Referencing

A good system of indexing also ensures easy cross-referencing and thus saves time and worries.

3. Economy

The cost of records management shall be reduced and the efficiency is also increased. Hence, a good index ensures economy in records management.

Types of Index Systems

According to J.C. Denyer, there are five main types of index, which are commonly used in all offices. They are:

  1. Page Index.
  2. Loose or Vertical Card Index.
  3. Visible Card Index.
  4. Strip Index.
  5. Rotary Index.

Though there are other methods of indexing, they are not taken up here for discussion, as they are crude, unscientific and unsystematic methods.

1. Page Index

This consists of a few pages allotted to each alphabet, fitted with a tab showing the letter. On each page are written the beginning with that letter and quoting the relevant reference, usually a number. This type of index is commonly used for the minutes, customers and suppliers’ ledgers etc.

Forms of Page Index

This type of indexing may take the following two forms:

1. Book Index

Book index may also be called bound index. Index is prepared alphabetically, in a bound book or register. The pages cannot be lost or disarranged as they are bound. If it is maintained as a separate book, the entries under different alphabets will indicate the file numbers of different persons. But if it is attached with some book say a ledger, it will indicate the pages of the ledger in which accounts of different persons have been entered into.

Book indexes are available in the market, and hence they are economical. But it will not be useful after a certain limit. Thus, it is inflexible. It can accommodate only limited number of entries. Another defect of this system is that the names are entered on each page in the order in which they first occur. Hence, a dictionary like sequence is not maintained. Therefore, it may take much time to locate an item.

2. Loose-leaf Book Index

A loose-leaf index is one in which pages are held by a device which makes it possible for the pages to be taken out or additional pages inserted. The sheets of papers are fitted on metal hinges and screwed. When a metal leaf is to be inserted or an old leaf is to be removed, the book is unscrewed and the relevant sheet is inserted or removed.

Merits of Page Index

1. It is a very simple method and easy to operate.

2. It is also a cheap method. So sophisticated equipment are not needed.

Demerits of Page Index

1. This system is very inconvenient.

2. Easy and quick reference are impossible.

3. When names are deleted the names should be strike off and this will present a shabby appearance.

4. This system is inflexible. Though loose-leaf binders offer certain amount of flexibility, this system cannot operate beyond a limit.

In spite of the drawbacks, this system of indexing is popular in small concerns all over the world. This system can also be successfully used even in large organizations for limited purpose.

2. Loose or Vertical Card Index

The loose card index was developed by Abbe Jeen Rozier, a Frenchman, to do away with the drawbacks of ordinary page index in the 18th century itself.

Under this method, separate cards of uniform size are allotted for each subject, customer or document. These cards are generally of 105 x 148 mm or 74 x 105 mm size. These cards contain the names and other particulars to be indexed. These cards are filed vertically and contain reference numbers on the top.

The cards are filed in some order say alphabetical, numerical or any other suitable method. They are placed in drawers or boxes of suitable dimensions. A hole is punched into each card and a steel rod runs through the cards so that the cards are kept in proper places. Guide cards are used to indicate the broad classifications such as letter A to Z or numerical sections.

This system is widely used in banks, libraries, hospitals and in offices for credit records and staff records.

Merits of Vertical Card Index

This system has several points to its credit. The most important ones are given below:

1. It is highly economical. Hence, complex equipment is not needed to install this system.

2. This system is highly flexible. New cards can be inserted at any time, without disturbing the original order.

3. This system is simple and easy to understand. Hence, trained staff need not be employed.

4. Dead cards can be removed very easily without disturbing the order.

5. Similarly, cards can be regrouped at any time within a short period.

6. Cross-referencing is easy and time is not wasted to have a cross-reference.

7. The card contains full particulars. Hence, one card is enough to gather as many information as needed.

8. This system can be used for various purposes and uses. This will lead to standardization of equipment and procedures.

9. More than one person can consult the card index at the same time.

Demerits of Vertical Card Index

This system has certain inherent defects. They are:

1. Cards can be substituted to commit or conceal fraud.

2. Constant supervision is needed to avoid fraudulent substitution or manipulation. Moreover, the cards taken for reference should  be reinserted in the same place. If the card is misplaced, the entire system will fail to produce the desired results.

3. Frequent handling of all cards shall result in frequent damage of cards. Hence, damaged cards or cards torn should be replaced by new cards from time to time.

4. There is also a danger of separate cards being lost by the persons who take them away from the drawers for reference.

5. Ready reference often becomes a difficult task.

In spite of the apparent defects, this system is highly flexible and simple to operate. In particular, this system is followed in all big libraries.

3. Visible Card Indexing

Under this method, the cards are laid flat in transparent covers in a shallow tray or in a metal frame. Each card is fitted into metal hinges so that the edge of each card projects the width of one line beyond edge of the next card. This makes possible to read one line on each card without turning the card.

According to J.C.Denyer,

The principle of all visible card is that the cards overlaps so that one line of entry on each card projects and is visible thus forming a one line index.

The trays in which the cards are kept are fitted with a device which enables the cards to he held in that position and yet permits individual cards to be written upon, withdrawn, replaced or rearranged whenever needed. The frames or trays can be attached vertically to the metal stands or they can be put horizontally into cabinets. The trays normally contain 50 cards.

Advantages of Visible Card Index

This system has some advantages namely,

1. It occupies less space and hence economical.

2. Instant or ready reference is ensured. Thus they can be referred to with speed, which adds to the efficiency of the office.

3. This system is highly flexible. In the same space, more cards can be removed without disturbing the original order.

4. Additional information can be easily written on this card without disturbing the order in which they are kept.

5. Controlling of various functions shall be made effective. Hence, this index is highly useful to the management in the process of controlling the affairs of the office.

Disadvantages of Visible Card Index

This system also has some defects such as:

1. The equipment required for this system is costly.

2. Trained staff should be employed for operating this system.

However, the equipment is not so costly, when compared to other sophisticated equipment. Hence in most modern offices, this system is widely used. Time studies in U.S.A. have shown that it is possible to locate cards by this system in one fourth of the time necessary for looking card under other non-visible systems. Thus, a saving of 75% time is ensured. Hence, most offices, in U.S.A. have opted for this system.

Recent Developments in Visible Card Indexing System

Some important variations were made in the visible card system so as to make it more useful. Some innovations made in this field are:

1. Automatic Card Index

Under this system, trays of card are suspended from a revolving mechanism under push bottom control by means of which the office staff can obtain quick access to more than one lakh cards.

2. Visible Books

Overlapping visible index record can also be kept in a book form. A visible book consists of a loose-leaf index in which pages are arranged like the cards in the visible card index.

3. Staggered Card Index

This system has been developed to give easier reference to the headings. Cards are arranged in groups and overlap so that reference headings on the cutaway corners of a whole group can be seen at once. This system of indexing is sometimes applied to ledger cards to facilitate the extractions of accounts for posting.

4. Strip Index

Strip index, in fact, is a type of visible card indexing which is used when the entries are limited to a few lines (Names, addresses etc.). In every type of office, a list of the names, address and telephone numbers is to be maintained. The strip index is specially designed for this purpose.

It consists of a frame into which strips of stiff paper covered by transparent plastic can be fitted. Limited lines can be written on the strip, as such short reference can be provided. Each strip is devoted to one correspondent, one file or one item. Frames fitted with strips can be fixed on the walls or arranged on a rotary stand. The strip can be protected from exposure or damage with removable transparent, celluloid or plastic window sheets.

Strip indexing offers similar advantages and suffers from the same drawbacks as those of visible card indexing.

5. Wheel or Rotary Index

The wheel or rotary index is a fairly recent development aimed primarily at saving space and time for reference. This system of index is very popular in Western countries. In fact, it is a modified form of visible card index.

Under this system, cards are arranged about the circumference of a wheel which may be portable or set in a cabinet or desk. Entries can be made on the card without removing the card from the wheel. Similarly, new cards can be inserted without any delay and without disturbing other cards.

A single wheel can hold nearly 5,000 cards and six wheels can be set up within the easy reach of the clerk sitting at his desk. The capacity can be further increased when wheels of a bigger diameter are arranged without disturbing the other cards, and entire scan is made on the card without removing them from the wheel. The rotary index may also take the form of a drum.

Advantages of Wheel Index

1. This system offers a greater speed of reference and thereby promotes the efficiency of office systems.

2. Economy in space requirements.

3. This system is highly flexible than to other systems.

4. Entries can be made in the card without removing them from the wheel.


A great advantage of visible index is that various control features can be introduced by the use of signals on the exposed edges of the records.

A signal can be described as a metal clip (Plastic tab or adhesive material which is attached to the exposed edge of the records). The principal aim of the signals is to draw the attention to certain fact records on the cards. The location of a particular folder or record ledger etc. can be made easier by attaching signals to them.

Its shape, colour or position along the edge of the folder, card or sheet shows the significance of a signal. However, these signals are only supplement to the main classification.

Choice of a Suitable Index System

So far we have discussed the basic methods of indexing in detail. But all methods are not at all suitable to all organizations. Sophisticated methods like wheel indexing are not suitable to small organizations. Hence, the most suitable system should be decided with reference to the requirements of the individual filing system. The factors to be considered are:

1. Volume of information wanted on the index.

2. The frequency of withdrawals and insertions.

3. Nature and number of entries made every day.

4. Cost of the equipment.

5. Space requirements and the availability of space.

6. The need for the use of signals.