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2 1 Introduction

From Bits to Zettabytes
A “bit” is the smallest unit of information possible. One bit has two pos-
sible values: 1 (on) and 0 (off). A “byte” is composed of 8 bits and can
8
represent 2 = 256 values. To talk about larger amounts of data, multi-
ples of 1000 are used: 1 Kilobyte (KB) equals 1000 bytes, 1 Megabyte
(MB) equals 1000 KB, 1 Gigabyte (GB) equals 1000 MB, 1 Terabyte (TB)
equals 1000 GB, 1 Petabyte (PB) equals 1000 TB, 1 Exabyte (EB) equals
1000 PB, and 1 Zettabyte (ZB) equals 1000 EB. Hence, 1 Zettabyte is
10 21 = 1,000,000,000,000,000,000,000 bytes. Note that here we used the In-
ternational System of Units (SI) set of unit prefixes, also known as SI prefixes,
rather than binary prefixes. If we assume binary prefixes, then 1 Kilobyte is
2 10 = 1024 bytes, 1 Megabyte is 2 20 = 1,048,576 bytes, and 1 Zettabyte is
2 70 ≈ 1.18 × 10 21 bytes.

Most of the data stored in the digital universe is unstructured and organizations
have problems dealing with such large quantities of data. One of the main challenges
of today’s organizations is to extract information and value from data stored in their
information systems.
The importance of information systems is not only reflected by the spectacular
growth of data, but also by the role that these systems play in today’s business pro-
cesses as the digital universe and the physical universe are becoming more and more
aligned. For example, the “state of a bank” is mainly determined by the data stored
in the bank’s information system. Money has become a predominantly digital entity.
When booking a flight over the Internet, the customer is interacting with many orga-
nizations (airline, travel agency, bank, and various brokers), often without actually
realizing it. If the booking is successful, the customer receives an e-ticket. Note that
an e-ticket is basically a number, thus illustrating the alignment between the digi-
tal and physical universe. When the SAP system of a large manufacturer indicates
that a particular product is out of stock, it is impossible to sell or ship the product
even when it is available in physical form. Technologies such as RFID (Radio Fre-
quency Identification), GPS (Global Positioning System), and sensor networks will
stimulate a further alignment of the digital universe and the physical universe. RFID
tags make it possible to track and trace individual items. Also note that more and
more devices are being monitored. For example, Philips Healthcare is monitoring
its medical equipment (e.g., X-ray machines and CT scanners) all over the world.
This helps Philips to understand the needs of customers, test their systems under
realistic circumstances, anticipate problems, service systems remotely, and learn
from recurring problems. The success of the “App Store” of Apple illustrates that
location-awareness combined with a continuous Internet connection enables new
ways to pervasively intertwine the digital universe and the physical universe.
The growth of a digital universe that is well-aligned with processes in organi-
zations makes it possible to record and analyze events. Events may range from the
withdrawal of cash from an ATM, a doctor setting the dosage of an X-ray machine,
a citizen applying for a driver license, the submission of a tax declaration, and the