ISO 9000

It is a family of standards for quality management systems. ISO 9000 is maintained by ISO, the International Organization for Standardization and is administered by accreditation and certification bodies. Some of the requirements in ISO 9001 (which is one of the standards in the ISO 9000 family) would include:
a set of procedures that cover all key processes in the business;
monitoring processes to ensure they are effective;
keeping adequate records;
checking output for defects, with appropriate corrective action where necessary;
regularly reviewing individual processes and the quality system itself for effectiveness; and
facilitating continual improvement
A company or organization that has been independently audited and certified to be in conformance with ISO 9001 may publicly state that it is "ISO 9001 certified" or "ISO 9001 registered." Certification to an ISO 9000 standard does not guarantee the compliance (and therefore the quality) of end products and services; rather, it certifies that consistent business processes are being applied.
Although the standards originated in manufacturing, they are now employed across a wide range of other types of organizations. A "product", in ISO vocabulary, can mean a physical object, or services, or software. In fact, according to ISO in 2004, "service sectors now account by far for the highest number of ISO 9001:2000 certificates - about 31% of the total"

[edit] ISO 9000 family
ISO 9000 includes the following standards:
ISO 9000:2005, Quality management systems - Fundamentals and vocabulary. Covers the basics of what quality management systems are and also contains the core language of the ISO 9000 series of standards. A guidance document, not used for certification purposes.
ISO 9001:2000 Quality management systems - Requirements is intended for use in any organization which designs, develops, manufactures, installs and/or services any product or provides any form of service. It provides a number of requirements which an organization needs to fulfill if it is to achieve customer satisfaction through consistent products and services which meet customer expectations. It includes a requirement for the continual (i.e. planned) improvement of the Quality Management System, for which ISO 9004:2000 provides many hints.
This is the only implementation for which third-party auditors may grant certification. It should be noted that certification is not described as any of the 'needs' of an organisation as a driver for using ISO 9001 (see ISO 9001:2000 section 1 'Scope') but does recognise that it may be used for such a purpose (see ISO 9001:2000 section 0.1 'Introduction').
ISO 9004:2000 Quality management systems - Guidelines for performance improvements. covers continual improvement. This gives you advice on what you could do to enhance a mature system. This standard very specifically states that it is not intended as a guide to implementation.
There are many more standards in the ISO 9001 family (see "List of ISO 9000 standards" from ISO), many of them not even carrying "ISO 900x" numbers. For example, some standards in the 10,000 range are considered part of the 9000 family: ISO 10007:1995 discusses Configuration management, which for most organizations is just one element of a complete management system. ISO notes: "The emphasis on certification tends to overshadow the fact that there is an entire family of ISO 9000 standards ... Organizations stand to obtain the greatest value when the standards in the new core series are used in an integrated manner, both with each other and with the other standards making up the ISO 9000 family as a whole".
Note that the previous members of the ISO 9000 family, 9001, 9002 and 9003, have all been integrated into 9001. In most cases, an organization claiming to be "ISO 9000 registered" is referring to ISO 9001.

Advantages

It is widely acknowledged that proper quality management improves business, often having a positive effect on investment, market share, sales growth, sales margins, competitive advantage, and avoidance of litigation
The quality principles in ISO 9000:2000 are also sound, according to Wade and Barnes, who says "ISO 9000 guidelines provide a comprehensive model for quality management systems that can make any company competitive." Barnes also cites a survey by Lloyd's Register Quality Assurance that indicated ISO 9000 increased net profit, and another by Deloitte-Touche that reported that the costs of registration were recovered in three years. According to the Providence Business

News implementing ISO often gives the following advantages:

• 
  Create a more efficient, effective operation
  Increase customer satisfaction and retention
  Reduce audits
  Enhance marketing
  Improve employee motivation, awareness, and morale
  Promote international trade

However, a broad statistical study of 800 Spanish companies found that ISO registration in itself creates little improvement because companies interested in ISO have usually already made some type of commitment to quality and were performing just as well before registration.
In today's service sector driven economy, more and more companies are using ISO 9000 as a business tool. Through the use of properly stated quality objectives, customer satisfaction surveys and a well-defined continual improvement program companies are using ISO 9000 processes to increase their efficiency and profitability.

ISO 14000

The ISO 14000 environmental management standards exist to help organizations minimize how their operations negatively affect the environment (cause adverse changes to air, water, or land), comply with applicable laws, regulations, and other environmentally oriented requirements, and continually improve on the above.
ISO 14000 is similar to ISO 9000 quality management in that both pertain to the process (the comprehensive outcome of how a product is produced) rather than to the product itself. The overall idea is to establish an organized approach to systematically reduce the impact of the environmental aspects which an organization can control. Effective tools for the analysis of environmental aspects of an organization and for the generation of options for improvement are provided by the concept of Cleaner Production.
As with ISO 9000, certification is performed by third-party organizations rather than being awarded by ISO directly. The ISO 19011 audit standard applies when auditing for both 9000 and 14000 compliance at once.

Occupational Health and Safety Management Systems (OHSMS)

Health and safety are important aspects of an organization’s smooth and effective functioning. Good health and safety performance ensures an accident-free industrial environment.

Awareness of Occupational Health and Safety (OH&S) has improved in India considerably. Organizations have started attaching the same importance to achieve high OH&S performance as they do to other key aspects of their business activities. This demands adoption of a structured approach for the identification of hazards, their evaluation and control of risks. BIS decided to formulate an Indian Standard on OH&S management systems considering this fact and a great demand from the industry for a comprehensive framework of OH&S.

IS 18001:2000 Occupational Health and Safety Management Systems – Specification with Guidance for use.

This standard prescribes requirements for an OH&S Management Systems to enable an organization to formulate a policy and objectives, taking into account legislative requirements and information about significant hazards and risks, which the organization can control and over which it can be expected to have an influence, to protect its employees and others, whose health and safety may be affected by the activities of the organization. All the requirements in this standard are intended to be incorporated into any OH&S management system. This standard also provides informative guidance on the use of the specification.