Overview
Every letter you type, every emoji you send, every character on this screen exists inside a computer as a sequence of 0s and 1s — binary code. The letter "A" is 01000001. The letter "Z" is 01011010. In this project you'll learn how ASCII encoding converts text to binary, then turn your name (or any short word) into a physical artifact: a bracelet where dark beads represent 1s and light beads represent 0s.
The bracelet is functional as well as decorative — someone who knows binary can read your name by looking at the bead pattern. It's a conversation starter, a way to wear a piece of computer science on your wrist, and a surprisingly effective way to memorize how binary numbers work.
What You'll Learn
- How binary numbers represent values using powers of 2
- How ASCII encoding maps characters to binary numbers
- How to convert a decimal number to binary and back
- Why computers use binary rather than decimal
- What a byte is and why 8 bits became the standard unit
Background
Computers store text using encoding standards — the most common historically is ASCII (American Standard Code for Information Interchange), which maps each character to a 7-bit binary number. Modern systems use UTF-8, which extends ASCII for international characters, but the first 128 characters are identical.
In binary, each digit (bit) represents a power of 2. Reading right to left: the first bit is 2⁰ (1), the second is 2¹ (2), the third is 2² (4), and so on. The number 01000001 = 0×128 + 1×64 + 0×32 + 0×16 + 0×8 + 0×4 + 0×2 + 1×1 = 65, which is the ASCII code for uppercase A.
This is the same system your computer uses for everything: text, file names, source code. Understanding binary is the first step toward understanding how all digital information is represented.
Safety note: No significant hazards. Young children should use round beads with large holes and be supervised when using a beading needle.
Materials
Everything on this list is either free or available at a dollar store. No lab equipment required.
Step-by-Step Procedure
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1
Learn Binary Numbers
Before you touch a single bead, make sure you can convert letters to binary. Look up an ASCII chart and find the binary code for the first letter of your name. Practice converting it: take the 8-bit code and add up the place values of each 1 bit. Example: A = 01000001 = 64 + 1 = 65. Now go back from 65 to binary: 65 ÷ 2 = 32 remainder 1; 32 ÷ 2 = 16 remainder 0; continue until you reach 0. Read the remainders from bottom to top.
Practice with at least 3 letters before moving to step 2.💡Binary conversion feels impossible the first time and automatic the fifth. Don't rush past this step.
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2
Plan Your Bracelet on Paper
Write out each letter of your name. Under each letter, write its 8-bit ASCII binary code. Under each bit, write D (dark bead) for 1 and L (light bead) for 0. Count the total beads needed: letters × 8, plus separator beads if you want them between letters.
Measure your wrist and calculate how many beads you need to go all the way around (typically 6–8mm beads fit 20–24 per average adult wrist). If your name won't fit, consider encoding just your initials.💡Plan completely on paper before stringing a single bead. Restringing a half-finished bracelet is the most frustrating part of this project.
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3
Cut and Prepare Your Thread
Cut a length of elastic cord about 3 times your wrist circumference — you need slack for working and tying. Thread your needle if using one. String a single bead and pull it to the center of the cord to act as an anchor while you build.
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4
String the Beads
Follow your paper plan exactly, bead by bead. String from left to right: the leftmost bit of each letter goes on first. After completing all 8 beads of a letter, optionally add one separator bead in a third color before starting the next letter.
After every 8 beads, hold the bracelet up and compare the dark/light pattern to your paper plan. Catching an error now is much easier than after 32 beads.💡Check every letter as you finish it, not just at the end.
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5
Finish and Test
Once all beads are on, wrap the bracelet around your wrist to check the fit — it should slip on comfortably with slight stretch. Tie a secure double knot and trim the excess cord. Tuck the knot between beads if you can.
Final test: hand your ASCII chart to a friend and ask them to read your bracelet. Can they decode your name?
Expected Results
Each letter in your name requires 8 beads (one byte). A four-letter name needs 32 beads plus any spacer beads between letters. Your finished bracelet should be readable by anyone with an ASCII chart — they can decode your name bead by bead.
If a letter decodes incorrectly, recount from the leftmost bead of that letter and check whether you have exactly 8 beads and whether the dark/light pattern matches the binary code you intended.
Your results may differ — and that's valuable data, not a mistake. Document what you actually observed, not what you expected.
Going Further
Encode a Secret Message
Make a bracelet for a friend that encodes a secret word. Give them the bracelet without telling them what it says — only give them the decoding key (dark = 1, light = 0, read ASCII chart). Can they decode it?
Write a Binary Converter
In Scratch or Python, write a program that accepts a name as input and outputs the binary ASCII code for each letter. Compare your program's output to what you encoded in your bracelet.
Explore Other Encodings
Research UTF-8 encoding. Why does an emoji require 4 bytes (32 bits) while a letter only needs 1 byte (8 bits)? How many different characters can be represented with 4 bytes?
