# Byte - Computer storage Unit

The byte is the smallest unit of computer storage and represents 8 bits.

Computer storage capacity is measured in bytes.

In today’s large-capacity servers, gigabyte is more often used.

## 3 - Management

### 3.1 - Id and Storage location

Accessing an individual byte frequently requires reading or writing a word at once

### 3.3 - Unit

You must use the binary notation for the computer resource (memory, disk)

• 100 Mb = 100 * 1024 * 1024 = 100 * 10242 = 104 857 600 byte
Decimal Binary
Value Si Value IEC JEDEC
1000 k kilo- 1024 Ki kibi- K kilo-
10002 M mega- 10242 Mi mebi- M mega-
10003 G giga- 10243 Gi gibi- G giga-
10004 T tera- 10244 Ti tebi-
10005 P peta- 10245 Pi pebi-
10006 E exa- 10246 Ei exbi-
10007 Z zetta- 10247 Zi zebi-
10008 Y yotta- 10248 Yi yobi-

### 3.4 - Conversion

#### 3.4.1 - Decimal

A `byte` is also an integer between:

• `0` in bit: `0000000`
• and `255` in bit: `1111111`.

#### 3.4.2 - Conversion Table

```function numberRepresentation(binary, decimal, hexadecimal) {
this.binary = binary;
this.decimal = decimal;
}
numbers =[]
for (var i=0;i<=16;i++) {
numbers.push(
new numberRepresentation(
i.toString(2),
i,
i.toString(16).toUpperCase()
)
);
}
console.table(numbers);```

## 4 - How Large is a Trillion?

```1 Kilobyte = 103 = 1000 bytes
1 Megabyte = 106 = 1,000,000 bytes
1 Gigabyte = 109 = 1,000,000,000 bytes
1 Terabyte = 1012 = 1,000,000,000,000 bytes
1 Petabyte = 1015 = 1,000,000,000,000,000 bytes
1 Exabyte = 1018 = 1,000,000,000,000,000,000 bytes
1 Zetabyte = 1021 = 1,000,000,000,000,000,000,000 bytes
1 Yottabyte = 1024 = 1,000,000,000,000,000,000,000,000 bytes

1 million seconds = 11.57 days
1 billion seconds = 31.6 years
1 trillion seconds = 31,688 years

1 million inches = 15.7 miles
1 trillion inches = 15,700,000 miles (30 round trips to the moon)

\$1 million = < \$ .01 for every person in U.S.
\$1 billion = \$ 3.64 for every person is U.S.
\$1 trillion = \$ 3,636 for every person in U.S.```