It’s a Binary World!
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Felipe H Razo Ph.D.

California State University East Bay
Hayward, Ca., 94544, USA


Counting and numbers, as a way to deal with the right amounts of things and their changes around us, in the best ways possible, seem to have been with us forever. For this reason, through time, we have learned to deal with the environment by imagining quantities of objects, phenomena and their changes as consisting of groups of smaller, equal-sized, similar “unit” parts, joined, grouped and ungrouped together conveniently and consistently to act together. We have learned to use helpful objects and symbols to aid us in imagining and communicating amounts and relationships. Over time, we have learned to use convenient material objects, tokens, artifacts, symbols, images, numerals and numbers organized in effective forms, understandings, practices and languages, including mathematics and supported by various tools of technology.

Historically, having ten fingers in our hands, readily available to help describe, communicate and manipulate quantities and numbers seems to have motivated our preference for counting subtance as items in small and large buildup groups of ten. This natural circumstane has resulted in the widely used decimal, or “Base 10” counting system we know today. Recently, however, rapidly evolving electronics and industrial technologies have resulted in a shift to almost all quantity information, operations and communications not being performed in Base 10 nor directly by humans, but instead by devices and machines using a numeric system that is more efficient for the purposes of automation. This numeric system groups items and multiples in groups of two units rather than ten, and is conceptually the simplest possible. This is called the "binary" or Base 2 system.

Today, quantity and other information is overwhemingly created and managed in the Base-2 binary numeric system. Translation into and out of the decimal system is mostly done, as necessary for the benefit of traditional, historic human communications. Indeed, it is a binary world out there. The question is: How proactive and consistent are we in educating ourselves, our children to properly and advantageously teach ourselves and our new generations learning about bases other than ten? In particular the binary Base 2 forms, as effective and efficiently as possible, from the earliest ages. This article proposes this to be not only desirable and feasible, but helpful for the development of motivation and confidence in quantitative thinking and acting within future “digital societies.”


Through history, our survival has depended on our abilities to perceive, imagine, and transform the environment [1]. These abilities have been related to the intelligent use of images, symbols and numbers, to make things more efficient, safer, cheaper, faster, better. The better the representations and manipulations of objects and actions, the better we can understand, and manage them.

We use representations to help us understand, imagine and transform the environment by counting, measuring size, form and qualities of objects, groups, and actions. We measure by considering quantities as collections or "counts" of simple, identifiable discrete, identical consecutive “basic unit”amounts of "like substance" that are joined together to make up some unified amount or “total” quantity [3]. Through careful selection, representation and manipulation of these representations, counting and measurement can be made as accurate (free of error) and precise (reliably repeatable outcomes) as possible, so we can do the things we do better. Through convenient images, symbols, arrangements and manipulations, we can record, communicate and process information in more effective (purposeful) and efficient (cheaper, faster, and safer) ways [5].

Through history, different civilizations have designed a variety of number systems for counting, to keep track of the size or effect of things, by aggregating (putting together), disaggregating (separating) or modifying quantities of substance, using consistently various symbols and procedures to represent and imagine what is possible to stay safe and satisfy our needs and abilities. As mentioned previouly, the most successful number systems in our past seem to have taken advantage of us having five, ten fingers (digits) in our hands, readily available to represent, communicate and manipulate simple quantities.

The Ancient Egyptians (about 2,500 BC) used strokes and icons of special objects in units and groups that are multiples of ten ( During the old Babylonian empire (about 1,800 BC), scribes carved scratches on clay tablets to record numbers representing terms of formal commercial transactions. The old babylonian culture seemed to have focused particularly in groupings of 10, 12 and 60 units ( Research in history indicates that our current scales for measuring angle degrees (30, 90, 180, 360 degrees) and time (12, 24 hours, 30 days) were influenced by the Babylonian counting systems and evidence exists that the calculation of diagonals of rectangular triangles in trigonometry was performed by the Babylonians using their 60's counting system some four thousand years ago (two millennia before the greek philosopher Pythagoras declared his triangle-sides theorem).

The Chinese (about 500 BC) used a variety of formal and informal sets of characters to represent numbers for different occasions, mostly using groupings of 10 ( Indeed the common abacus design seems to reflect much of the structure of counting and number manipulations in ancient China.

The Greek ( and the Roman ( number systems used elaborate combinations of symbols and letters to describe their numbers, while the Mayans (about 1,000 AD) used dots and lines, mostly to relate to moon cycles, seasons, and passage of time in general.

The Mayan counting system emphasized using the numbers 5 and 20 as a basis for counting the number of days in their month. The Mayan system also refered to other time events and preceded most other systems in recognizing and explicitly including the number zero (conch,) to signal the absence of quantity (,g_1:history:gmsOcjJITWI%3D,online_chips:mayan+mathematics:Lf0XMV-1uNI%3D&hl=en&sa=X&ved=2ahUKEwiZjMO3_Kr4AhUIATQIHYo_DrkQ4lYoBnoECAEQLQ&biw=1845&bih=972).

The ancient Roman system relied on letter symbols to represent groups in numbers approaching or following around 5 (V=5) or 10, such as X=10, L= 50, C=100, D=500, M=1000. The non-trivial, “additive” or subtractive” form of placing adjacent symbols in groups of the Roman number system presented obvious shortcomings, particularly as compared with the contemporary, simpler, more effective Hindi-Arabic, base 10 or "decimal system" we are most familiar with and described next.

Eventually, and due to advantages of having ten fingers (digits) in our hands, as well as the simplicity of uniform, consistent groupings (i.e. bundling) of units and symbol usage (nine groups and a zero-null symbol) through size, number systems converged into the current decimal system. This system, which has also improved through time is still prevalent today, although mostly for common human events is called the Hindu-Arabic, or “Base 10 system”.

NOTE: A "base" in a number system is the maximum number of unit items that can be counted up in each digit position, before being considered bundled and counted as a unit-bundle part in the next, higher position digit. Such positions are known as “place values”.

In the Base 10 or decimal counting system , there are only ten basic symbols (1, 2, 3, 4, 5, 6, 7, 8, 9, and zero), which are used repeatedly in a series of ordered positions to signify the number of units (or "bundles") of increasingly higher value, each position (place value) to the left being ten times greater than the previous one (….10000, 1000, 100, 10, 1.0, 0.1, 0.01, ….., etc.). The quantities indicated by the stated digit in each position has therefore a value ten times greater (or smaller) than the ones following next to the right or left (i.e. ….., x1000, x100, x10, x1, ÷10, ÷100, ÷1000, …. etc).

Recently, however, accelerated developments in science and technology, particularly in electromagnetism, electronics and materials have led a shift to a number system based in only two symbols, typically represented by a zero, and a one (0, 1). Conveniently, these two symbols correspond to each of two distinct, reliably defined and manipulated physical states of electronic, magnetic and/or optical materials and devices. The system is called binary, or Base 2 number system, and it is conceptually the most efficient way of using a distinctive physical characteristic of objects to represent information [7]. For numbers beyond 1, the binary system uses combinations of its two basic symbols, arranged in sequential space-ordered positions, representing multiples of its Base 2. Similar to the decimal system, the positions represent "bundles" that increase in value from the right to the left by multiples of 2 (i.e. …, 32, 16, 8, 4, 2, 1, ½, ¼, ⅛, 1/16, 1/32, …..etc.).

Because of the massive gains in efficiency and speed in producing, manipulating, and communicating number and other information, binary representations are used today for practically all automated operations, with translation into the decimal system done only when human communication and participation is absolutely necessary.

Still, and in spite of its importance, relative simplicity, and potential learning benefits, today the binary system seems to be a topic absent from most general curricula of K-12 educational institutions. The question is: Why? and then, what are the consequences of this absence?


Up to now, teaching to count and manipulate quantities in our elementary and high-school (K-12) classrooms has been focused exclusively on the Base 10 system. While this would have been appropriate in the past, when there was no justified alternative, how appropriate is this narrow focus for today and tomorrow's changing times and needs?

Understandably, up to now, a focus on the Base 10 system has helped educate citizens to operate competently in a decimal world. But with dramatic shifts in technology, industry, socioeconomic and even personal, home activity towards heavy reliance on automated measurement, communications, calculation and control of processes, the abilities to design, produce, and apply corresponding products and new tools can very well determine the future personal, industrial and commercial survival, success and dominance of individuals, organizations and nations.

As key quantitative abilities begin to develop (or not) in our minds and bodies during the earlier years in our lives [8], perhaps it would be helpful to reconsider our basic elementary education, boldly but carefully. Like most successful, large-scale projecs, the objectives, way and means for stronger foundations of basic modern number and computation development in our children should be opportunely provided.

What would it take, and what could it mean to add the topic of bases other than 10 in the early, elementary and high school (preK-12) curricula?

First, to promote general numeracy, proven successful approaches, such as starting with smaller numbers and repeated, multisensory counting practice should always be considered. Then, providing more opportunities to leverage student motivation for learning in context [9, 10], participative skill development [11], and community building [12] should be considered, such as proper use of appropriate, available technologies alternatives to increase student involvement and understanding through multiple and more accessible media [13], visual sharing, group chanting, participation and interaction experiences. More issues related to the use of current technologies for learning and teaching can be found at: Teaching and Learning with Technology in Elementary and Secondary Classrooms (DOCUMENT, FRazo, 2010)

Following ahead are examples of teaching activities for the concepts of place value, number bases, and the Base 2 number system. Although these activities were designed and field tested with careful consideration to the various factors affecting learning, also included in the TPACK Technical, Pedagogical, and Content Knowledge frame [17], up to now there have been no opportunities for large-scale testing of these activities in order to demonstrate sufficient statistical significance of their effects. Still, the evidence gathered so far through repeated experiences [14, 15, 16] point to consistent increases in student appreciation of the process of counting under different base systems, as well as of their understanding of the invariant concepts for number systems and operations under different bases.


As an example of different representations of a number in alternative groupings or bases, the number 13 is shown, side-to-side, in corresponding place-value representations in Bases 10, 5, and 2 in Fig 1 below. The same 13 items are therefore shown grouped in corresponding bundles of multiples of ten, five, and two items.

"13" in base 10 = "23" in base 5 = "1101" in base 2

Fig 1 Different Bases – Grouping 13 Items by 10’s, 5’s, and 2’s

The images and links in Figure 2 below display interactive web pages on the Internet featuring 13 items to be counted in virtual animations of counting objects (cubes or pebbles), as they are gradually counted and grouped consistently in increasingly larger size bundles. These activities can be used in standard Internet-enabled computers, interactive touch-screen panels and larger "smart boards" so as to view, access and interact with (virtual) objects and scenarios, while counting, observing, modifying and learning the ensuing patterns repeatedly, inexhaustibly, efficiently and safely.




The number 13 In Base 10: 13 = 10+3

The number 13 In Base 5: 13 = (2*5) + 3

The number 13 In Base 2: 13 = 8 + 4 + 1
For practice:

Fig 2. Representing the number 13 with counters in groupings of 10, 5 and 2

The following link is to an image of a physical operating electronic counter, designed and built by a 10th grade student, using a common binary counter microchip and common, standard components: (binary counting electronic panel). The panel was designed and built for students to experience and internalize the counting process in binary and decinal forms, using physical electronics, industrial components.


The topic of fractions, typically a challenging one when introduced in the middle elementary and higher grades, could also be supported by relating them to their representation in bases other than 10. In Figure 3, the decimal number 23.675 is used to present the place value concept for fractional amounts (right of the units point), both in Bases 10 and 2. In Figure 4, an ancient clay tablet can be used to illustrate how an old civilization used highly accurate fractional representations of whole and fractional quantities in their then-prevalent Base 60 numeric system. The 2 decimal places (1/10, 1/100) in the decimal counter can represent only one-hundredth-of-a-unit (0.01) block increments, whereas in the binary counter with 3 fractional places (½, ¼, ⅛) can only represent quantities in one-eight of-a-unit block increments (0.125). The binary representation that uses only 3 fractional digits is known as binary point eight, and has been used extensively in the approximated, high-speed measurement of remote (telemetry) high voltage electrical infrastructures.



Fractions in Base 10

Fractions in Base 2

For practice:

Fig 3 Representation of the number 23.675 with fractional parts in Base 10 and in Base 2

To reduce the limitations fraction representations due to arbitrary place-value partitioning (e.g. “thirds”-0.333…, , pi-3.1415, all “irrational numbers”, ...) or to the limited number of digits provided by available computing devices (e.g. device available “decimal counters”, “binary word” bits, ...), more elaborate forms have been developed, such as doubling the number of digits, approximating, or multiplying numbers by a scaling factor (“logarithmic” scaling in decimal devices, "double word" or "floating point" in binary computers). These and other important topics could be made appropriate and feasible, in some simplified, illustrative form, at least for initial understanding and motivational discussion, beginning in the primary and secondary grades.

The use of place value concepts to represent and manipulate fractional quantities would show much significantly, appropriate, and ancient than suspected, as students observe and explore samples like the interactive web page of Figure 4 below, where a clay tablet, made some 4,000 years ago in current-day Irak, during the old-Babylonian Empire. The clay tablet displays symbols and calculations describing the size and relationship between sides in right triangles involving fractional parts. The numbers, are stated in a then-prevailing Base 60 number system, and correspond to a calculation commonly assumed to have been first stated as the "Pythagorean Theorem", some 2,000 years later. The buttons to the right of the page allow the students to see how the Babylonians represented the square root of the numbers 2, and 1,800 represented in the Base 60 system.


Old Babylonian Base 60

Fig 4 Fractions from our ancestors, some 3,700 years ago

Next, the activity in Figure 5 below, titled "Inter Bases Converter" lets students enter a number in Base 10, to be seen expanded, approximated as possible in available digits for two other equivalent base representations, for comparison including up to five fractional digits.


Inter-bases Converter

Fig 5 Equivalent Representation with fractional parts in Different Number Bases

Fraction representations are also quite useful in the binary, base-2 system. The activity in Figure 6 presents an interactive process called binary successive approximation method, which is widely implemented with “digital” circuitry to describe electrical quantities representing measurements in the environment. Measurement quantities represented in binary forms are often referred to as digital measurements. Digital measurements of from the environment (size, weight, temperature, pressure, etc.) are created by first producing corresponding electric voltages in physical devices called sensors or transducers (converters to electrical voltage) and then evaluated in special devices called digital meters.

Digital meters typically compare received voltages to some internally generated reference value, typically by a process of either accumulation (ramping) of known-size unit pulses, or by comparing with an accumulation of all, successively smaller binary fraction reference voltages within the instrument capacity range (successive approximation) while not exceeding the received voltage level. The successive approximation method, is illustrated in the interactive activity of Figure 6 below. A measuring comparison sequence begins from the left by successively comparing the received external voltage with succesive binary fractions of the internal voltage range, adding each value to the internal reference-total only while the received voltage is not surpassed, until all the binary digit fractions (½, ¼ ,1/8, 1/16, 1/32, etc.) are exhausted.

In the interactive activity of Figure 6, the electrical voltage of a measurement (sensor) source is stated through a slide-knob (left) in the first page and then, in the second page, a successive approximation process is allowed. The process shows how selecting successively smaller binary segments of voltage results in a fast measurement value. The process stops when a match condition is detected, or when all the binary fraction digits are exhausted.


Binary successive approximation method

Fig 6 Binary successive approximation method for electrical measurement


Figure 7 below illustrates the process of addition and subtraction of two numbers in Base 2, step by step, using both symbols and visual virtual objects. The animated activity displays meaningful objects (pebbles) depicting digit-by-digit ordered place value joining and regrouping in traditional right-to-left order into larger bundles (carrying), similarly as it is commonly done in the traditional Base 10 system. Today, addition, subtraction and all simple and complex quantity operations are performed with numbers, and overwhelmingly with tools consisting of electromagnetic and electronic arrays and procedures (algorithms) supported by basic electronic components and assemblies.

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