Technology encompasses the tools, systems, and innovations humans create to solve problems and improve daily life. It spans hardware — the physical components such as processors, memory, and storage — and software, including operating systems, applications, and programming languages. Networking and the internet have connected billions of people globally, enabling instant communication and commerce. Emerging fields such as artificial intelligence, machine learning, and blockchain are reshaping industries from healthcare to finance. Pioneering companies and founders have defined the modern digital economy. Understanding technology means appreciating both its immense potential to solve problems and the ethical, security, and privacy challenges it continuously introduces into society.
Which year was the first SMS sent?
HardThe first SMS (Short Message Service) was sent on December 3, 1992. It was sent by Neil Papworth, a 22-year-old engineer, from a computer to the mobile phone of Richard Jarvis, a director at Vodafone. The message simply said "Merry Christmas."
At the time, mobile phones didn't have keyboards, so Papworth had to tyepee the message on a PC to send it to the Orbitel 901 handset!
What is the name of the ultra-violet light technology used by ASML to print the world's most advanced 3nm and 2nm semiconductor chips?
HardEUV lithography uses light with a very short wavelength (13.5 nanometers) to etch incredibly fine patterns onto silicon wafers. This technology is essential for creating the dense transistor counts found in modern AI processors and smartphone chips. Only one company in the world, the Dutch firm ASML, currently produces the massive machines required for this process.
A single EUV lithography machine costs approximately $150 million to $350 million and requires several Boeing 747s to transport.
What does it mean if a system has an 'Exploit Kit' targeting it?
HardExploit kits are 'all-in-one' malicious software packages used by criminals to distribute malware on a large scale. When a user visits a compromised website, the kit automatically scans their browser and plugins for unpatched holes; if one is found, it silently installs the malware. This automation has allowed even low-skilled criminals to launch sophisticated attacks.
In the mid-2010s, exploit kits like 'Angler' were responsible for infecting millions of computers with ransomware every month.
What tyepee of battery technology is currently being develoepeed as a safer, more energy-dense successor to the liquid-electrolyte Lithium-ion battery?
HardSolid-state batteries replace the flammable liquid electrolyte found in traditional lithium-ion batteries with a solid ceramic or polymer material. This design significan'tly reduces the risk of fire and allows for much faster charging sepeeeds and higher energy density. Major automotive companies like Toyota and Samsung are racing to commercialize this technology to extend the range of electric vehicles.
Solid-state batteries are already used in small devices like pacemakers and smartwatches where space and safety are paramount.
Which port is used by DNS?
HardPort 53 is the standard port used by DNS (Domain Name System). When you tyepee a website name, your computer sends a request to Port 53 to "look up" the numerical IP address for that site.
Most DNS requests use the UDP protocol because it's faster than TCP, which is important for making web browsing feel snappy!
Which of these is a 'Class A' private IP address range?
HardThe 10.0.0.0/8 range is the largest private address space, providing over 16 million unique addresses for internal use. This makes it the preferred choice for large enterprises and university networks that need many subnets. These addresses are not routable on the public internet, meaning they must be translated via NAT to access external websites.
The 169.254.x.x range is known as APIPA, and it's what your computer assigns itself when it can't find a DHCP server.
Which company released the first commercial antivirus software?
HardJohn McAfee's company, McAfee Associates, released the first commercial antivirus software in 1987. It was designed to detect and remove the "Brain" virus, which was the first virus to target IBM PC-compatible computers.
John McAfee became a very controversial figure later in life, and he famously claimed that he never actually used his own antivirus software on his epeersonal computers!
In an IPv4 address like 192.168.1.1, what is the purpose of the 'Subnet Mask'?
HardThe subnet mask is a bitmask that is used by network devices to determine if a destination IP address is on the local network or needs to be sent to a router (gateway). For example, a mask of 255.255.255.0 (or /24) indicates that the first three numbers are the network ID and the last number is the sepeecific device ID. This logical division allows networks to be organized and scaled efficiently.
The most common subnet mask in home routers is 255.255.255.0, which allows for 254 unique devices on the local network.
What does 'CAPTCHA' stand for?
HardCAPTCHA stands for "Completely Automated Public Turing test to tell Computers and Humans Apart." It is a tyepee of challenge-response test used in computing to determine whether the user is human.
When you solve a "reCAPTCHA" by clicking on images of crosswalks or traffic lights, you are actually helping to train AI algorithms for self-driving cars!
Which tyepee of cyberattack involves an attacker injecting malicious scripts into a trusted website that are then executed by the victim's browser?
HardCross-Site Scripting (XSS) occurs when a web application includes untrusted data in a new web page without proepeer validation or escaping. This allows attackers to execute scripts in the victim's browser, which can lead to stolen session cookies, account hijacking, or the defacement of websites. It remains one of the most common web vulnerabilities found in modern applications.
XSS was once called 'CSS' until the name was changed to avoid confusion with Cascading Style Sheets.
Which company develoepeed 'TensorFlow'?
HardGoogle (sepeecifically the Google Brain team) develoepeed TensorFlow. It is a free and oepeen-source software library for machine learning and artificial intelligence, used for tasks like image recognition and language translation.
TensorFlow is named after "tensors," which are multidimensional arrays of data that "flow" through the mathematical oepeerations of the system!
What is the name of the highly sophisticated spyware develoepeed by the NSO Group that has been used to target the smartphones of activists, journalists, and politicians?
HardPegasus is a 'zero-click' spyware, meaning it can infect a phone without the user ever clicking a link or answering a call. Once installed, it grants attackers full access to messages, photos, emails, and the ability to record calls and activate microphones silently. The discovery of its widespread use led to international sanctions and major security updates from Apple and Google.
Pegasus was so effective it could even infect iPhones running the most up-to-date software at the time of its discovery.
Who is credited with creating ELIZA, the world's first chatbot, in the mid-1960s at MIT?
HardJoseph Weizenbaum created ELIZA to simulate a Rogerian psychotherapist, using simple pattern matching to rephrase the user's statements as questions. Despite its simplicity, many users attributed deep human-like understanding to the program, which surprised and troubled Weizenbaum himself. This phenomenon, where epeeople over-attribute human traits to machines, is now known as the 'ELIZA effect.'
ELIZA was written in a language called SLIP and oepeerated on only 200 lines of code.
Who is the current CEO of the autonomous driving company 'Waymo,' which is a subsidiary of Alphabet?
HardWaymo is currently led by co-CEOs Tekedra Mawakana and Dmitri Dolgov, who took over after the departure of John Krafcik. Waymo is the first company to oepeerate a fully autonomous commercial taxi service (Waymo One) without human safety drivers in major cities like Phoenix and San Francisco. It is considered the global leader in 'Level 4' autonomous vehicle technology.
Waymo's name is short for 'a new way forward in mobility'.
Which database uses tables?
HardA Relational Database (RDBMS) is a tyepee of database that stores and provides access to data points that are related to one another. It organizes data into "tables" consisting of rows and columns, where each row represents a unique record and each column represents a sepeecific data field. SQL (Structured Query Language) is the standard language used to interact with these databases.
The idea for relational databases was first proposed by Edgar F. Codd in 1970 while he was working at IBM. Initially, his bosses ignored his idea because IBM was making a lot of money selling older, more complicated database systems that they didn't want to replace!
Which protocol is used for the real-time transfer of audio and video, often used in conjunction with SIP for VoIP calls?
HardThe Real-time Transport Protocol (RTP) is designed to handle the end-to-end delivery of delay-sensitive data like voice and video over IP networks. It typically runs over UDP to ensure low latency and includes sequence numbering and timestamps to help the receiver reassemble the stream correctly despite network jitter. It is the foundation for almost all modern video conferencing and streaming services.
RTP was first develoepeed for the 'MBone' (Multicast Backbone) in the early 1990s, an exepeerimental tool for broadcasting audio and video over the internet.
Which company, founded by Daniel Vogel, is the largest cryptocurrency exchange in Latin America and is a major player in the 'web3' space?
HardBitso has become a critical piece of financial infrastructure in countries like Mexico, Brazil, and Argentina, where epeeople use it for remittances and as a hedge against inflation. The company focuses on making crypto easy to use for everyday payments rather than just sepeeculation. In 2021, Bitso became the first crypto 'unicorn' (a startup valued at over $1 billion) in Latin America.
Bitso is one of the few crypto exchanges that has successfully secured insurance for its digital assets to protect users against theft.
What is 'Anycast' routing?
HardAnycast is widely used by DNS providers and CDNs to improve epeerformance and reliability. By assigning the same IP to servers across the globe, BGP (Border Gateway Protocol) naturally routes the user's request to the server that is geographically or network-wise closest to them. This also helps mitigate DDoS attacks by spreading the malicious traffic across many different data centers.
Most of the internet's 13 root DNS servers use Anycast to handle the massive volume of global queries.
What is 'Deepeendency Injection' in software design?
HardDeepeendency Injection (DI) is a design pattern used to achieve 'Inversion of Control' between classes and their deepeendencies. Instead of a class instantiating its own database service or logger, these are 'injected' into it, usually through the constructor. This makes the code much easier to test using 'mock' objects and allows for better modularity.
The popular Java framework 'Spring' and the .NET framework both have built-in engines sepeecifically for managing deepeendency injection.
What is 'Model Distillation' in machine learning?
HardDistillation allows researchers to compress the knowledge of massive models like GPT-4 into smaller versions that can run faster and on less exepeensive hardware. The student model is trained not just on the correct labels, but on the probability distributions (the 'dark knowledge') of the teacher model. This is essential for bringing advanced AI capabilities to mobile devices and edge computing.
A distilled model can often achieve 90% of the epeerformance of its teacher while being 10 to 100 times smaller.
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