Cloud, IoT, Blockchain, 5G and More
Cloud computing
Using servers, storage and software over the Internet and paying for what you use. Benefits: scalability, no hardware to maintain, access from anywhere.
| Service model | You get | Example |
|---|---|---|
| IaaS | Infrastructure: servers, storage | Amazon EC2, Azure VMs |
| PaaS | Platform to build apps | Google App Engine |
| SaaS | Ready-made software | Gmail, Google Docs, Microsoft 365 |
Deployment: public (shared, run by a provider), private (one organisation), hybrid (both), community. Big providers: AWS, Microsoft Azure, Google Cloud. India's government cloud is MeghRaj (GI Cloud). Virtualisation runs several virtual machines on one physical machine. Edge computing processes data near where it is made.
Internet of Things (IoT)
Everyday objects with sensors, software and Internet connection that collect and exchange data: smart meters, smart homes, wearables, connected cars. The term was coined by Kevin Ashton (1999). RFID and NFC are short-range tags used in toll cards and contactless payment.
Blockchain
A distributed ledger: records (blocks) are linked by hashes, copied across many computers and almost impossible to alter. It needs no central authority and works by consensus. Bitcoin (Satoshi Nakamoto, 2008 paper, 2009 launch) is the first cryptocurrency. Smart contracts are self-running agreements on a blockchain (Ethereum). A cryptocurrency is digital money secured by cryptography.
Mobile generations
| Generation | Feature |
|---|---|
| 1G | Analog voice |
| 2G | Digital voice and SMS (GSM, CDMA) |
| 3G | Mobile internet, video calls |
| 4G (LTE) | Fast broadband, HD video |
| 5G | Very high speed, very low latency, millions of devices per square km |
5G was launched in India on 1 October 2022. SIM = Subscriber Identity Module. IMEI is the 15-digit serial number of a phone.
Other technologies
| Technology | Meaning |
|---|---|
| Quantum computing | Uses qubits, which can be 0 and 1 together (superposition) and linked (entanglement). India's National Quantum Mission was approved in 2023. |
| AR / VR | Augmented Reality adds digital items to the real view; Virtual Reality is a fully digital world. |
| 3D printing | Builds objects layer by layer from a digital model. |
| Drones | Unmanned aerial vehicles. |
| Digital twin | Virtual copy of a real object or system. |
| GPS / NavIC | GPS is the US navigation system; NavIC is India's regional system (ISRO). |
| Green computing | Energy-saving computing. E-waste is discarded electronics. |
Keep practising
Notes are only half the work. Test yourself with questions and discuss doubts with other aspirants.
Prepared for exam revision from standard computer textbooks, Microsoft documentation and official sources. Features differ between Excel and Word versions (2016, 2019, 2021, 365) so check which version your exam follows. Found a mistake? Tell us.