Secret codes (2024)

In this video, Dr. Yossi Elran explains about the connection between mathematical operators and two kinds of secret codes.

View transcript

So, we’ve talked a lot about operators on numbers, We’ve even spoken a bit about logic operators. What about operators on letters? Well, it’s funny. Operators on letters, really change the letters, and make something that is legible - illegible! This is a nice way of thinking about secret codes. What are secret codes? You take a sentence, a phrase, a paragraph, even a word, encrypt it - that’s the operator, and you get something that you cannot read. There are many, many kinds of secret codes. In fact, secret codes are so broad a topic, that you’re going to have to do a course which hopefully we’ll create, that is totally dedicated to secret codes.

56.4

However, I want to give you just a small taste of two kinds of secret codes, and they differ in the way that we operate on or manipulate the letters.

66.8

We’re going to do this with an example of this famous sentence: “Ground control to Major Tom”. One kind of an encryption is called substitution - substitution cipher. In a substitution cipher you substitute every letter in the plaintext with another letter. This is very, very well known, even appears in the bible, Julius Caesar used it a lot and it’s called a Caesar cipher. Here’s a very, very simple example, where we’ve just encrypted every letter in “Ground control to Major Tom” into the letter that comes afterwards. So G goes into H, R to S, O to P, U to V, N to O, D to E and so on. Each letter with the letter after it.

127.3

So, from “Ground control to Major Tom” we get a sentence: HSPVOE, DPOUSPM, UP, NBKPS, UPN. And of course that’s illegible. Of course, it’s not difficult to decipher this or to crack this code, because it pops up immediately that each letter is encrypted by the letter, previous. It can be made more difficult by shifting each letter 3 or 17 forwards or backwards or even just randomly associating each letter with another letter or another number, and this is just an archetype of substitution ciphers.

171.9

Notice here also, another way of deciphering these codes, is by using statistics and seeing for instance that there’s a lot of O’s over here and in the sentence that corresponds to having a lot of P’s here in the scrambled message. That’s one kind of operation, substitution. Another kind of operation is called transposition. In transposition, you take a sentence and transpose it, mix it up.

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So, this sentence over here: GDRMT, RCOAO, OOLJM, UNTOX, NTORX is the sentence “Ground control to Major Tom” with the letters scrambled in different order. You can see that the same letter O which is dominant in the original sentence “Ground control to Major Tom”, is also dominant in the message, in the encrypted message, so it’s the same letters but they’re all scrambled up. And this is the way we scrambled them, we just wrote them inside a 5 by 5 table and then we wrote it in the rows and drew out the numbers in the columns.

253.5

So, “Ground control to Major Tom” and the X’s just fill in the blanks at the end is written in the rows and we draw out the letters

269.3

in the columns: GDRMT, RCOAO, OOLJM, UNTOX and NTORX. So we’re going to give you a very small challenge on secret codes to end the course.

This is where all that we have learnt comes together. Secret codes. First, to get a brief introduction, please take time to watch the short video.

Secret codes can be viewed as a symbology, except that now different symbols encode letters instead of numbers. These symbols can be signs (like Morse code or Braille which are just encodings and not ‘secret’), or they can be other letters, or even the same letters themselves.

One can encode a message letter by letter, exchanging each letter with another symbol (these are substitution ciphers), or one can encode the whole message by scrambling up the order of the letters in the message (transposition ciphers).

But when we encrypt a message what are we really doing? We are operating on text with an operator that transforms the text into another symbology.

And when we want to try and break a code we have to work out what the symbology is and also what the encoding operator does. In other words, given an illegible encoded text, we have to work out what the operator is – is it a substitution cipher or a transposition cipher and how does the operator work? And we also have to work out the symbology in order to ‘break’ the secret code.

Cryptography is a huge topic in mathematics with many day-to-day applications, that deserves a full-fledge course. Still, I would like to challenge you with two secret codes, one a transposition and the other a substitution code that I have made up and see if you can ‘break’ the codes. I’m just going to give you the secret messages, and you can ‘break’ them for yourselves. I also have a special request – make up your own secret code, write it down in the discussion and let us all try and ‘break’ the codes. Here are my two:

Message 1:

TELLH NAROW OIANY WTEEO DTEVO HKMTI
WLSWE YUERI EOHNI ITIRO PTLGA NEKNT
AWWUA HDHDD SLKTR OHABE SLIIK

HINT: First create an empty rectangular box 15×6. The first column of the rectangular box should contain 15 letters, the other columns should contain only 14 letters.

Message 2:

PDUBK DGDOL WWOHO DPEOL WWOHO DPEOL WWOHO DPEPD UBKDG DOLWW OHODP ELWVI OHHFH ZDVZK LWHDV VQRZ

Good Luck!

This article is from the online course:

Maths Puzzles: Cryptarithms, Symbologies and Secret Codes

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Secret codes (2024)

FAQs

Secret codes? ›

2. *#*#7780#*#* (Run a Factory Reset) If you don't want to run a hard reset, this is the next best thing. Similar to a factory reset, this code will simply delete all application data from your device, as well as any applications.

What does * * 7780 * * do? ›

2. *#*#7780#*#* (Run a Factory Reset) If you don't want to run a hard reset, this is the next best thing. Similar to a factory reset, this code will simply delete all application data from your device, as well as any applications.

What is * * 4636 * * code used for? ›

*#*#4636#*#* Displays information about the phone, battery, and various network statistics.

What does *# 7353 do? ›

*#7353# – Open the Quick test menu. *#*#273282*255*663282*#*#* – Make a backup of your media files. *#*#7780#*#* – Factory reset your Android phone.

How to crack a secret code? ›

All substitution ciphers can be cracked by using the following tips:
  1. Scan through the cipher, looking for single-letter words. ...
  2. Count how many times each symbol appears in the puzzle. ...
  3. Pencil in your guesses over the ciphertext. ...
  4. Look for apostrophes. ...
  5. Look for repeating letter patterns.
Sep 27, 2021

What is *# 2767 * 3855? ›

Use the code *2767*3855# to delete all data and reset all settings on your #Samsung phone #MobileTip #MoArmouz | Coding, Phone, Samsung.

What does ## 002 do to your phone? ›

##002# - If your voice call or data call, or SMS call has been forwarded, dialling this USSD code will erase them. *#21# - By dialling this USSD code, you would get to know if your calls have been diverted somewhere else or not.

What is code *# 0011? ›

Battery status (ADC, RSSI reading) *#0011# Service Menu.

What is 3370? ›

By pressing *3370# or #3370#, you'll activate your phone's “reserve battery power”. Battery life will increase by 50%. The reserve will automatically charge up the next time you change your device. Other claims state dialing the same sequence will boost cellular reception.

What is the use of *# 0 *# code? ›

Key hardware info: *#0*#

When you enter *#0*# into the phone's dialer, the device enters service mode and brings up a diagnostics menu. From this screen, you can view and run multiple diagnostics to test device hardware like buttons, sensors, and cameras.

What is *# 21 code used for? ›

According to tech magazine How-To Geek, dialing this code shows whether or not call forwarding is enabled on the device — not whether it's been hacked. How-to Geek described the *#21# feature as an “interrogation code” that allow users to view their call forwarding setting from the phone app.

What is *# 61 used for? ›

With the *#61# settings interrogation code, you can see if calls are being forwarded to another number whenever they go unanswered. If the "Voice Call Forwarding" and "Data Call Forwarding" say they're disabled, that's good.

What is *# 06 and other codes? ›

Display your IMEI: *#06#

It also worked on my Android AT&T device as well. To access it, type in the above code, and then the green call button to prompt your IMEI number (or your International Mobile Station Equipment Identity number, but you already knew that). The IMEI is unique to your device.

What is the secret code 2789? ›

TikTokers are using the code to convey the message "I'm tired of life" in their videos, comments, or in their bios. Hence, 2789 means “I'm tired of life.” It is unclear who started this code or how it gained traction once again.

What is the hardest code to hack? ›

AES ‍ One of the hardest codes to crack is arguably the US government's Advanced Encryption Standard (aka Rijndael or AES) which the Americans use to protect top-secret information. AES is considered unbreakable by even the most sophisticated hackers.

What are hacks in code? ›

As a noun, a hack is source code in a program. For example, the phrase "it must be done through a hack" means someone has to write programming code to solve the problem because there is no pre-written software that does the job.

What is * 68 used for? ›

Dialing *68 will disable the Caller ID for the next outbound / external call only. Selecting a line and dialing this feature code will result in a prompt on the phone display as well as an audible message: "Caller ID is BLOCKED for the next outbound call only." We hope you find this new feature code useful!

What happens to your phone when you dial *# 9900? ›

The *#9900# code is a diagnostic mode code for Samsung mobile devices. It can be used to access a variety of system information and diagnostic tools, such as enabling/disabling fast dormancy, logging options, and system dump mode.

What device is b140dl? ›

$49. Please select a payment option. Introducing the BLU View 3, filled with amazing features such as 32GB internal memory paired with 3GB RAM, Android 11 OS, battery friendly Octa-Core processor, and much more.

What does ## 004 do? ›

Call “##004#”

No one will answer when you call it, but it will turn off conditional forwarding on your phone. It will reset your phone to its default phone settings.

What is the 3 digit number to see if your phone is tapped? ›

Code to check if phone is tapped: *#21# Code to show unknown connections and tracking (for Android): *#*#4636#*#* or *#*#197328640#*#*

What is the code to see if your phone is hacked? ›

Use the code *#21# to see if hackers track your phone with malicious intent. You can also use this code to verify if your calls, messages, or other data are being diverted. It also shows your diverted information's status and the number to which the information is transferred.

What does *# 30 do on Android? ›

#2 NUMBER IDENTIFICATION: The code *#30# will help you turn your number identification on or off.

How to use Android secret code? ›

There are two ways to execute a secret code: Directly through the dialer application of your Android device. Simply write the secret code like: *#*#123456789#*#* . String secretCode = "123456789"; Intent intent = new Intent(Intent.

What is the 8 digit unlock code for Samsung? ›

First of all, insert the SIM card and turn your device on. Type the code *#9998*3323# and Exit.

What does * 3001 12345 #* mean? ›

Accessing Field Test Mode on an iPhone can be quite straightforward: simply go to your phone's dialer, type in *3001#12345#* and hit the dial button.

What is *# 31? ›

Hide Caller ID: *31#

The caller might have hidden the ID intentionally or sometimes it can be accidental. If you want to hide the caller ID dial *31# and press call button.

How does *# 06 work? ›

For a Google Pixel, dial *#06# on your phone's keyboard to get the IMEI number. For phones with a removable battery, some IMEI numbers are listed on a sticker under the battery on the back of the phone.

What is +1 code used for? ›

1 – United States, including United States territories: 1 (340) – United States Virgin Islands.

What is *# 0 *# on iPhone? ›

*#0*# - This will take you straight to the General Test Mode once dialed from the Phone app. It lets you test a bunch of things on your iPhone, such as vibration, touch, speaker etc. *5005*7672# - Dial this one up and you'll be presented with your SMS message center number.

What is * 74 on your phone? ›

Establish a short list of up to eight numbers, or a longer list of up to 30 numbers. To program your Speed Calling 8 list, dial *74. Listen for the dialtone, then dial the one-digit number (2 through 9) you would like to use to dial a frequently called number.

What is the iPhone trick *# 21? ›

What does dialing *#21# actually do? When you dial *#21#, you are, in fact, activating a feature access code that quickly tells you the status of call forwarding for your phone. It's a quick way of seeing what, in the case of this particular 'setting interrogation code,' your call forwarding settings.

Can you check if your phone is tapped with *# 21? ›

You can find out if your phone has been tapped using unconditional data forwarding with the help of MMI codes. On GSM networks, dial *#21# to list, and ##21# to clear your unconditional data forwarding settings. CDMA network customers can view and modify these settings too by dialing **21*.

What does * 78 do on your phone? ›

Activates the Do Not Disturb feature. When active, the user's phone does not ring and all calls go directly to a "busy treatment" such as Voice Messaging. Lift the telephone handset, press the speaker button, or the headset button. Dial the code *78, then #.

What does * 57 do on your phone? ›

Activate Call Trace

Hang up the phone after receiving a harassing call. Pick up the phone and press *57 (touch tone) or 1157 (rotary). You'll hear a confirmation tone and message will be heard If the trace is successful.

What does * 97 do on a phone? ›

The next time you receive a call from a number you wish to block, end the call and dial *97. The number will automatically be added to your Selective Call Rejection list. You can block up to 100 numbers.

What is * 82 phone code? ›

This Vertical Service Code, *82, enables calling line identification regardless of subscriber preference, dialed to unblock withheld numbers (private callers) in the U.S. on a per-call basis.

What is * 70 on the phone? ›

*70 - Call Waiting: Places your call on hold so you can answer another. *72 - Call Forwarding: Forward your call to another phone number. *77 - Anonymous Call Rejection: Blocks calls from private callers.

What is 134 secret code? ›

In a certain code language, '134' means 'good and tasty'; '478' means 'see good pictures' and. '729' means 'pictures are faint'.

What is 477 secret code? ›

477: Best friends forever

Another one where you just add up the number of letters in each word.

What does 1423 mean in code? ›

The number combination 14/23 is a numeric symbol associated with the Southern Brotherhood, the largest white supremacist prison gang in Alabama.

What code do most hackers use? ›

C++ is one of the go-to C languages for hackers because it helps them gain low-level access to hardware and processes.

What code has never been broken? ›

The Dorabella Cipher

A code which remains unsolved to the present day was created by the acclaimed English composer Edward Elgar. The creator of Pomp and Circ*mstance wrote an enciphered letter in 1897 to Dora Penny, the daughter of a reverend whose stepmother was friends with Elgar's wife.

What is the hardest code to code? ›

The hardest code to crack is arguably the Advanced Encryption Standard (AES). It is the most widely used symmetric encryption algorithm, adopted by the US government for its top secret information, and considered unbreakable by even the most sophisticated hackers.

What are the 7 types of hackers? ›

Types Of Hackers
  • White Hat / Ethical Hackers.
  • Black Hat Hackers.
  • Gray Hat Hackers.
  • Script Kiddies.
  • Green Hat Hackers.
  • Blue Hat Hackers.
  • Red Hat Hackers.
  • State/Nation Sponsored Hackers.

What was the first hack? ›

The first hacking incident actually occurred before computers. Reportedly, the first hackers were from the year 1878. Shortly after the invention of the telephone and only two years after the start of Alexander Graham Bell's famous telephone company, young phone operators pranked callers by switching telephone lines.

Is it illegal to use hacks? ›

The United States is one of the countries where hacking is considered a crime. The Computer Fraud and Abuse Act (CFAA) is a US law that makes it illegal to access a computer without authorization.

What is the hidden menu on my phone? ›

Instead of tapping on the back of your phone or swiping a finger, this menu can be pulled up using the dialing pad. Here's how: Open the dialing pad as if you were making a phone call. Type *#0*#.

What is the master password to unlock any phone? ›

There is no master pin for an Android phone. Everything from 0000 1234 or whatever you can think of.

What are the Android secret codes? ›

Check out these Android secret codes
  • *#*#759#*#* - This code will let you access RIz debug UI.
  • *#0*# - This code will let you see the info menu.
  • *#*#4636#*#* - If the previous code does not work, you can see your info menu with this one.
  • *#*#34971539#*#* - This code will let you see your camera information.
Jan 20, 2023

What is the secret code for IMEI? ›

*#06# - This code will show your device's IMEI number. So, go ahead, test these android secret codes out and find the hidden info on your smartphone.

What are hidden apps used for? ›

Such hidden apps are intentionally hidden after being installed by the user itself, or they may be present on mobile phones as pre-installed apps. Also, it is found that Android itself installs some hidden apps on devices to maintain device productivity and security checks.

What does *# 21 do on Android? ›

What does dialing *#21# actually do? When you dial *#21#, you are, in fact, activating a feature access code that quickly tells you the status of call forwarding for your phone. It's a quick way of seeing what, in the case of this particular 'setting interrogation code,' your call forwarding settings.

What is the hard reset code for all phones? ›

Open the dialer/phone app on your device and input this code: *2767*3855# step 3. After that, follow the on-screen instructions to reset your device.

Is there a master code? ›

The MasterCode is a computer code that allows to fit different versions of the Minimal Supersymmetric Standard Model (MSSM) to currently existing experimental data.

What is *# 9900? ›

The *#9900# code is a diagnostic code used on Samsung mobile devices. It opens the "SysDump" mode, which provides advanced system information and options for troubleshooting and debugging purposes.

What is top secret code? ›

If the National Security Clearance Level is Top Secret, the position is designated as Critical Sensitive, FPPS Code 3.

What is a hidden menu app on Android? ›

It's called the System UI Tuner and it can be used for customizing an Android gadget's status bar, clock and app notification settings. Introduced in Android Marshmallow, this experimental menu is hidden but it's not difficult to find. Once you get to it, you'll wish you knew about it sooner.

What is the secret code *# 21? ›

Android Phone Hacks

Security of Android Smartphone codes : Code ## 002 # ~ Deactivates all forwarding. Code * # 21 # ~ To know whether message or call has been diverted or not. Code * # * # 4636 # * # * ~ To know Wifi connection test, Phone battery. Code * ## 62 # ~ To know whether phone redirects to any number.

Can any one hack with IMEI number? ›

Common misconceptions about IMEI

Using IMEI, a hacker cannot connect to your phone or have even the slightest bit of access to it. No one can get your calls or SMS on another device, Using IMEI. Using IMEI, a person cannot control your phone, or any apps installed.

What data can you get from IMEI number? ›

The basic information that an IMEI number holds is all about the device. This is hard-coded in when the number is created, going into depth about the make, model and specifications of the device it refers to. From this, a carrier can take a look at what the device is supposed to be able to do.

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