Biotechnology is technology based on biology, especially 
when used in agriculture, food science, and medicine. 
United Nations Convention on Biological Diversity defines 
biotechnology as:[1]

"Any technological application that uses biological 
systems, dead organisms, or derivatives thereof, to make or 
modify products or processes for specific use."

Biotechnology is often used to refer to genetic engineering 
technology of the 21st century, however the term 
encompasses a wider range and history of procedures for 
modifying biological organisms according to the needs of 
humanity, going back to the initial modifications of native 
plants into improved food crops through artificial 
selection and hybridization. Bioengineering is the science 
upon which all biotechnological applications are based. 
With the development of new approaches and modern 
techniques, traditional biotechnology industries are also 
acquiring new horizons enabling them to improve the quality 
of their products and increase the productivity of their 
systems.

Before 1971, the term, biotechnology, was primarily used 
within the agricultural industries. Current uses of the 
term generally refer to the technologies associated with 
genetic engineering as well as cell- and tissue culture.

A broad definition of biotechnology is "The application of 
indigenous and/or scientific knowledge to the management of 
(parts of) microorganisms, or of cells and tissues of 
higher organisms, so that these supply goods and services 
of use to the food industry and its consumers.[2]

In simple words biotechnology is any technological 
application which is used to make a change in a cell or in 
biological system. Biotechnology draws on the pure 
biological sciences (genetics, microbiology,animal cell 
culture,molecular biology, biochemistry, embryology, cell 
biology) and in many instances is also dependent on 
knowledge and methods from outside the sphere of biology 
(chemical engineering,bioprocess engineering, information 
technology, biorobotics). Conversely, modern biological 
sciences (including even concepts such as molecular 
ecology) are intimately entwined and dependent on the 
methods developed through biotechnology and what is 
commonly thought of as the life sciences industry

Biotechnology is a subject, which is combined with science &
technology.
    Biotechnology consists of biological agents such as
micro organisms and cellular organisms for beneficial use.

Biotechnology is the science that can alter the biological 
beings to benefit the human race.

Biotechnology in one form or another has flourished since 
prehistoric times. When the first human beings realized 
that they could plant their own crops and breed their own 
animals, they learned to use biotechnology. The discovery 
that fruit juices fermented into wine, or that milk could 
be converted into cheese or yogurt, or that beer could be 
made by fermenting solutions of malt and hops began the 
study of biotechnology. When the first bakers found that 
they could make a soft, spongy bread rather than a firm, 
thin cracker, they were acting as fledgling 
biotechnologists. The first animal breeders, realizing that 
different physical traits could be either magnified or lost 
by mating appropriate pairs of animals, engaged in the 
manipulations of biotechnology. 

What then is biotechnology? The term brings to mind many 
different things. Some think of developing new types of 
animals. Others dream of almost unlimited sources of human 
therapeutic drugs. Still others envision the possibility of 
growing crops that are more nutritious and naturally pest-
resistant to feed a rapidly growing world population. This 
question elicits almost as many first-thought responses as 
there are people to whom the question can be posed. 

In its purest form, the term "biotechnology" refers to the 
use of living organisms or their products to modify human 
health and the human environment. Prehistoric 
biotechnologists did this as they used yeast cells to raise 
bread dough and to ferment alcoholic beverages, and 
bacterial cells to make cheeses and yogurts and as they 
bred their strong, productive animals to make even stronger 
and more productive offspring. 

Throughout human history, we have learned a great deal 
about the different organisms that our ancestors used so 
effectively. The marked increase in our understanding of 
these organisms and their cell products gains us the 
ability to control the many functions of various cells and 
organisms. Using the techniques of gene splicing and 
recombinant DNA technology, we can now actually combine the 
genetic elements of two or more living cells. Functioning 
lengths of DNA can be taken from one organism and placed 
into the cells of another organism. As a result, for 
example, we can cause bacterial cells to produce human 
molecules. Cows can produce more milk for the same amount 
of feed. And we can synthesize therapeutic molecules that 
have never before existed.

science which deals with all technics based on bio study 
and biological alterations.

it's a branch of science in which -------- exploitation of
all natural resourses for human welfare.

COMMERCIAL EXPLOITATION OF BIOLOGICAL PROCESS OR USING OF 
BIOLOGICAL AGENT FOR HUMAN WELFARE.

Biotechnology is a Concept/Science of "EXPERIMENTING LIFE FOR LIFE........."

It is yesterdays science& todays technology.The biological
organisms are used to get desired products.