A BRIEF COMPUTER HISTORY
The computer as we know it today had its beginning with a 19th century English mathematics professor name Charles Babbage.
He designed the Analytical Engine and it was this design that the basic framework of the computers of today are based on.
Generally speaking, computers can be classified into three generations. Each generation lasted for a certain period of
time,and each gave us either a new and improved computer or an improvement to the existing computer.
First generation: 1937 – 1946 - In 1937 the first electronic digital computer was built by Dr. John V. Atanasoff and Clifford Berry. It was called the Atanasoff-Berry Computer (ABC). In 1943 an electronic computer name the Colossus was built for the military. Other developments continued until in 1946 the first general– purpose digital computer, the Electronic Numerical Integrator and Computer (ENIAC) was built. It is said that this computer weighed 30 tons, and had 18,000 vacuum tubes which was used for processing. When this computer was turned on for the first time lights dim in sections of Philadelphia. Computers of this generation could only perform single task, and they had no operating system.
Second generation: 1947 – 1962 - This generation of computers used transistors instead of vacuum tubes which were more reliable. In 1951 the first computer for commercial use was introduced to the public; the Universal Automatic Computer (UNIVAC 1). In 1953 the International Business Machine (IBM) 650 and 700 series computers made their mark in the computer world. During this generation of computers over 100 computer programming languages were developed, computers had memory and operating systems. Storage media such as tape and disk were in use also were printers for output.
Third generation: 1963 - present - The invention of integrated circuit brought us the third generation of computers. With this invention computers became smaller, more powerful more reliable and they are able to run many different programs at the same time. In1980 Microsoft Disk Operating System (MS-Dos) was born and in 1981 IBM introduced the personal computer (PC) for home and office use. Three years later Apple gave us the Macintosh computer with its icon driven interface and the 90s gave us Windows operating system.
As a result of the various improvements to the development of the computer we have seen the computer being used in all areas of life. It is a very useful tool that will continue to experience new development as time passes.
Computer Generations
Computer Generation:
There are five generations of computer:
• First generation – 1946 - 1958
• Second generation – 1959 - 1964
• Third generation – 1965 - 1970
• Fourth generation – 1971 - today
• Fifth generation – Today to future
The First Generation:
• The first computers used vacuum
tubes for circuitry and magnetic
drums for memory, and were often
enormous, taking up entire rooms.
• They were very expensive to operate
and in addition to using a great deal of
electricity, generated a lot of heat,
which was often the cause of
malfunctions.
• First generation computers relied on machine
language, the lowest-level programming language
understood by computers, to perform operations,
and they could only solve one problem at a time.
• Input was based on punched cards and paper tape,
and output was displayed on printouts.
The Second Generation
• Transistors replaced vacuum tubes
and ushered in the second generation
of computers.
• One transistor replaced the
equivalent of 40 vacuum tubes.
• Allowing computers to become
smaller, faster, cheaper, more
energy-efficient and more reliable.
• Still generated a great deal of heat
that can damage the computer.
• Second-generation computers moved from cryptic
binary machine language to symbolic, or assembly,
languages, which allowed programmers to specify
instructions in words.
• Second-generation computers still relied on punched
cards for input and printouts for output.
• These were also the first computers that stored their
instructions in their memory, which moved from a
magnetic drum to magnetic core technology.
The Third Generation
• The development of the integrated
circuit was the hallmark of the third
generation of computers.
• Transistors were miniaturized and
placed on silicon chips, called
semiconductors, which drastically
increased the speed and efficiency of
computers.
• Much smaller and cheaper compare
to the second generation computers.
• It could carry out instructions in
billionths of a second.
• Users interacted with third generation computers
through keyboards and monitors and interfaced with
an operating system, which allowed the device to
run many different applications at one time with a
central program that monitored the memory.
• Computers for the first time became accessible to a
mass audience because they were smaller and
cheaper than their predecessors.
There are five generations of computer:
• First generation – 1946 - 1958
• Second generation – 1959 - 1964
• Third generation – 1965 - 1970
• Fourth generation – 1971 - today
• Fifth generation – Today to future
The First Generation:
• The first computers used vacuum
tubes for circuitry and magnetic
drums for memory, and were often
enormous, taking up entire rooms.
• They were very expensive to operate
and in addition to using a great deal of
electricity, generated a lot of heat,
which was often the cause of
malfunctions.
• First generation computers relied on machine
language, the lowest-level programming language
understood by computers, to perform operations,
and they could only solve one problem at a time.
• Input was based on punched cards and paper tape,
and output was displayed on printouts.
The Second Generation
• Transistors replaced vacuum tubes
and ushered in the second generation
of computers.
• One transistor replaced the
equivalent of 40 vacuum tubes.
• Allowing computers to become
smaller, faster, cheaper, more
energy-efficient and more reliable.
• Still generated a great deal of heat
that can damage the computer.
• Second-generation computers moved from cryptic
binary machine language to symbolic, or assembly,
languages, which allowed programmers to specify
instructions in words.
• Second-generation computers still relied on punched
cards for input and printouts for output.
• These were also the first computers that stored their
instructions in their memory, which moved from a
magnetic drum to magnetic core technology.
The Third Generation
• The development of the integrated
circuit was the hallmark of the third
generation of computers.
• Transistors were miniaturized and
placed on silicon chips, called
semiconductors, which drastically
increased the speed and efficiency of
computers.
• Much smaller and cheaper compare
to the second generation computers.
• It could carry out instructions in
billionths of a second.
• Users interacted with third generation computers
through keyboards and monitors and interfaced with
an operating system, which allowed the device to
run many different applications at one time with a
central program that monitored the memory.
• Computers for the first time became accessible to a
mass audience because they were smaller and
cheaper than their predecessors.
The Fourth Generation
• The microprocessor brought the
fourth generation of computers, as
thousands of integrated circuits
were built onto a single silicon chip.
• As these small computers became
more powerful, they could be linked
together to form networks, which
eventually led to the development
of the Internet.
• Fourth generation computers also
saw the development of GUIs, the
mouse and handheld devices.
The Fifth Generation
• Based on Artificial Intelligence (AI).
• Still in development.
• The use of parallel processing and superconductors
is helping to make artificial intelligence a reality.
• The goal is to develop devices that respond to
natural language input and are capable of learning
and self-organization.
• There are some applications, such as voice
recognition, that are being used today.
Effects of Testosterone Treatment in Older Men
BACKGROUND:
Serum testosterone concentrations decrease as men age, but benefits of raising testos-
terone levels in older men have not been established.
METHODS:
We assigned 790 men 65 years of age or older with a serum testosterone concentration
of less than 275 ng per deciliter and symptoms suggesting hypoandrogenism to receive
either testosterone gel or placebo gel for 1 year. Each man participated in one or more
of three trials — the Sexual Function Trial, the Physical Function Trial, and the Vital-
ity Trial. The primary outcome of each of the individual trials was also evaluated in all
participants.
RESULTS:
Testosterone treatment increased serum testosterone levels to the mid-normal range for
men 19 to 40 years of age. The increase in testosterone levels was associated with sig-
nificantly increased sexual activity, as assessed by the Psychosexual Daily Questionnaire
(P<0.001), as well as significantly increased sexual desire and erectile function. The
percentage of men who had an increase of at least 50 m in the 6-minute walking dis-
tance did not differ significantly between the two study groups in the Physical Function
Trial but did differ significantly when men in all three trials were included (20.5% of
men who received testosterone vs. 12.6% of men who received placebo, P=0.003). Tes-
tosterone had no significant benefit with respect to vitality, as assessed by the Func-
tional Assessment of Chronic Illness Therapy–Fatigue scale, but men who received tes-
tosterone reported slightly better mood and lower severity of depressive symptoms than
those who received placebo. The rates of adverse events were similar in the two groups.
CONCLUSIONS:
In symptomatic men 65 years of age or older, raising testosterone concentrations for
1 year from moderately low to the mid-normal range for men 19 to 40 years of age had
a moderate benefit with respect to sexual function and some benefit with respect to
mood and depressive symptoms but no benefit with respect to vitality or walking dis-
tance. The number of participants was too few to draw conclusions about the risks of
testosterone treatment. (Funded by the National Institutes of Health and others;
ClinicalTrials.gov number, NCT00799617.)
Serum testosterone concentrations decrease as men age, but benefits of raising testos-
terone levels in older men have not been established.
METHODS:
We assigned 790 men 65 years of age or older with a serum testosterone concentration
of less than 275 ng per deciliter and symptoms suggesting hypoandrogenism to receive
either testosterone gel or placebo gel for 1 year. Each man participated in one or more
of three trials — the Sexual Function Trial, the Physical Function Trial, and the Vital-
ity Trial. The primary outcome of each of the individual trials was also evaluated in all
participants.
RESULTS:
Testosterone treatment increased serum testosterone levels to the mid-normal range for
men 19 to 40 years of age. The increase in testosterone levels was associated with sig-
nificantly increased sexual activity, as assessed by the Psychosexual Daily Questionnaire
(P<0.001), as well as significantly increased sexual desire and erectile function. The
percentage of men who had an increase of at least 50 m in the 6-minute walking dis-
tance did not differ significantly between the two study groups in the Physical Function
Trial but did differ significantly when men in all three trials were included (20.5% of
men who received testosterone vs. 12.6% of men who received placebo, P=0.003). Tes-
tosterone had no significant benefit with respect to vitality, as assessed by the Func-
tional Assessment of Chronic Illness Therapy–Fatigue scale, but men who received tes-
tosterone reported slightly better mood and lower severity of depressive symptoms than
those who received placebo. The rates of adverse events were similar in the two groups.
CONCLUSIONS:
In symptomatic men 65 years of age or older, raising testosterone concentrations for
1 year from moderately low to the mid-normal range for men 19 to 40 years of age had
a moderate benefit with respect to sexual function and some benefit with respect to
mood and depressive symptoms but no benefit with respect to vitality or walking dis-
tance. The number of participants was too few to draw conclusions about the risks of
testosterone treatment. (Funded by the National Institutes of Health and others;
ClinicalTrials.gov number, NCT00799617.)
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