Measurments in

Informatics.

Fátima Chamorro & Paula Ramírez.

It was added to the International System of Units (SI) in

1975. It has the unit symbol EB. Denoting a factor of

1018 or 1.000.000.000.000.000.000. Exa means six (like hexa) , because it is equal to 1.0006. Example: In 2004, the global monthly Internet traffic

passed 1 exabyte for the first time.

EXABYTE

 It was added in the International System of Units in

1975. It has the unit symbol PB. Denoting a factor of 1015 (1.000.000.000.000.000). Peta means five and because of that it is similar to the

prefix penta . Example:The 2009 movie Avatar is reported to have

taken over 1 petabyte of local storage at Weta Digital for the rendering of the 3D CGI effects.

PETABYTE

It was added ,for use in the SI,in 1960. It has the unit symbol TB. Denoting a factor of

 1012 or 1.000.000.000.000. Tera means ¨monster¨. For example:As of May 2009, Yahoo!

Groups had 40 terabytes of data to index.

TERABYTE

 The earliest written use of giga in this sense to

be in the Reports of the IUPAC 14th Conference in 1947.

It has the unit symbol GB. Denoting a factor of a (short-form) billion

(109 or 1.000.000.000). The binary prefix gibi has been adopted for 230,

while reserving giga exclusively for the metric definition.

A typical hard disk has a capacity of 500Gb

GIGABYTE

 It was confirmed for use in the International

System of Units (SI) in 1960. It has the unit symbol MB. Denoting a factor of one million

(106 or 1.000.000). Mega means ¨great¨. In early days, memory cards for devices had

only an amount of a few megabytes.

MEGABYTE

 It was originally adopted by Antoine

Lavoisier's research group in 1795, and introduced into the metric system in France in 1799.

It has the unit symbol kB. Denoting a factor of one thousand ( 1000) Kilo means ¨thousand¨. Ten years ago there were floppy disks instead

of pen drives with only 720 KB capacity

KILOBYTE

It was adopted as a multiplier in 1795. It has the unit symbol H. Denoting a factor of one hundred (100) Hecto means ¨hundred¨ Usain Bolt only takes 9,5 seconds for running

1 Hectometer

HECTO

The prefix was a part of the original metric

system in 1795. It has the unit symbol DA. Denoting a factor of ten. Deca means ¨ten¨. It is not in very common usage, although the

decapascal is occasionally used by audiologists. 

The blue whale is approximately 3 decameters in length.

DECA

BYTE

It was added in 1957 in the International System

It has the unit symbol B. Denoting a factor of 1. It consists of eight bits. The ASCII code (how internally are

represented letters in computers) represents each letter in one byte (8 bits)

 Adopted in 1795 in the International System. Its most frequent use is in the non-SI unit,

the decibel, used to measure sound intensity. It has the unit symbol d. Denoting a factor of 10-1 (0,1) Deci means ¨tenth¨. A CD diameter is about 1,2 decimeters.

DECI

It was added in the to the International

System in 1795. It has the unit symbol c. Denoting a factor of Centi means ¨hundred¨. It is mainly used to express  lengths

in centimetres A honeybee is about 1.3 centimeters in length.

CENTI

It was added in 1795 in the International

System. It has the unit symbol m. Denoting a factor of one thousandth (10-3). Milli means ¨one thousand¨ A snow crystal is about 1 millimeter in

diameter.

MILLI

 Confirmed in 1960. It has the unit symbol µ. Denoting a factor of 10−6 (one millionth). Micro means ¨small¨. Typical bacteria are 1 to 10 micrometers in

diameter. 

MICRO

It was officially confirmed as standard in 1960. It has the unit symbol n. Denoting a factor of 10−9 or 0.000000001. Nano means one billionth.  It is frequently encountered in science and

electronics. One nanometer is about the length that a

fingernail grows in one second.

NANO

It defined in 1960 when the International System of

Units was established. It has the unit symbol p. Denoting one trillionth, a factor of 10-

12(0.000000000001). Pico means peak, beak, bit. The radius of atoms range from ~25 picometers

(hydrogen) - 260 picometers (caesium).

PICO

FEMTO

Adopted by the 11th Conférence Générale des Poids et Mesures.

It has the unit symbol f. Denoting a factor of 10−15 or 0.000000000000001. Femto means "fifteen". The femtometre shares the unit symbol (fm) with the

older non-SI unit fermi, to which it is equivalent. A proton has a diameter of about 1.6 to 1.7

femtometres.

ATTO

The unit multiple was adopted at the 12th Conférence Générale des Poids et Mesures (CGPM) in Resolution 8.

It has the unit symbol a. Denoting a factor of 10−18 or

0.000000000000000001. Atto means "eighteen". Weight of the HIV-1 Virus is about 1 ag.

The End.

By Fátima Chamorro & Paula Ramírez.