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A 2.1.1 Network Purpose and Characteristics
A network is two or more devices connected so that they can exchange data. Networks differ enormously in size, from the link between a phone and its earbuds to the global internet, yet they all exist...
eBook
A 1.4.1 Interpreters and Compilers (HL Only) Free
A computer cannot run Python or Java source code directly. The processor understands only machine code, so every program written in a high-level language has to be translated first, and there is more...
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A 1.3.1-1.3.5 Operating Systems Free
Every program you run depends on a layer of software you almost never see. The operating system sits between your applications and the hardware, deciding which program runs next, where files are kept,...
eBook
A 1.2.5 Logic Diagrams
A logic diagram is a drawing of a circuit built from logic gates, with wires carrying binary signals from the inputs on the left to the output on the right. Learning to read and draw these diagrams is...
eBook
A 1.2.4 Truth Tables
A truth table lists every possible combination of inputs to a logic system and records the output for each one. This page shows how to build a truth table from a circuit and from a worded problem, how...
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A 1.2.3 Logic Gates
Logic gates are the components that let a computer act on binary signals rather than merely store or move them. Each gate takes one or two binary inputs and produces a single binary output according to...
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A 1.2.1-2 Representing Data
Everything a computer holds, a number, a sentence, a photograph, a song, is stored as a pattern of binary digits. This page covers two linked ideas: how whole numbers are written in binary and hexadecimal...
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A 1.1.9 Cloud Computing
Most of the software you used this week probably ran on someone else's computer. Cloud computing means renting computing resources over the internet, paying for what you use rather than buying and maintaining...
eBook
A 1.1.8 Compression
Every photo you send, every song you stream and every web page you load has almost certainly been compressed. Compression reduces the size of a file by representing the same information in fewer bits,...
Review/revision
B2.1 Broken Code challenges - Java
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