Choose an exam and explore concepts through visual explanations, topic maps and revision checks. Open the full chapter notes whenever you need more detail.
THE VISUAL LEARNING STUDIO
See the idea. Understand the connection.
35 visual explanations across 29 chapters, with topic maps throughout the library.
The chapter index will grow as additional notes are prepared. Chapters shown here are a learning collection, not a claim that the entire exam syllabus is complete.
SEE IT. CONNECT IT. EXPLAIN IT.
Understand the chapter visually
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Study the expanded notes and the credited detailed textbook lessons. The current chapter index covers core topics; it is not a claim of exhaustive coverage of every examination syllabus. Check the official syllabus and primary references.
Hardware, Memory and Internet Basics — lesson overview
Hardware and software
Hardware is the physical equipment of a computer system. Software consists of instructions and associated programs that direct its operations.
An operating system manages resources and provides services for programs. An application performs tasks such as word processing or browsing.
The CPU executes instructions; storage, memory, input, and output devices play different roles. A complete system cannot be understood by naming the processor alone.
Memory and storage
RAM typically provides working memory for active processes and is ordinarily volatile: its stored state is lost when power is removed. Non-volatile storage retains data without continuous power.
A bit is a binary digit. A byte commonly consists of eight bits. Distinguish capacity units from transfer-rate units and read the stated decimal or binary convention.
More storage space is not the same as more RAM. Performance depends on the workload and the interaction of processor, memory, storage, and software.
Internet, web and safe access
The internet is a network of networks. The World Wide Web is a service using web resources and protocols; it is not the entirety of the internet.
A URL identifies a resource. DNS helps map domain names to information such as IP addresses. A browser and a search engine are different tools.
HTTPS encrypts and authenticates the connection to the named site under its certificate system. A lock symbol alone does not prove that the site’s content or commercial offer is trustworthy.
