Input, Output and Memory Devices; Storage

Key Points at a Glance

1. 1

   The in-scope 2026 Senior Secondary CET Computer Knowledge bullet covers computer organization with memory, RAM, ROM, file system, input devices and output devices.

2. 2

   Input-process-output-storage is the basic working chain: input devices send data in, the CPU processes it, output devices present results, and storage keeps data for later use.

3. 3

   Keyboard, mouse, scanner and touchscreen are standard input examples; a touchscreen can be both input and output because it displays information and accepts touch.

4. 4

   Monitor, projector, speaker, printer and braille display monitor are output examples; printers give hard copy while monitors give soft copy.

5. 5

   RAM is volatile main memory used for active work; ROM is non-volatile memory associated with essential start-up instructions.

6. 6

   Cache memory is very fast memory close to the CPU; registers are small storage locations inside the CPU for immediate data, instructions or intermediate results.

7. 7

   Secondary storage such as HDD, SSD, pen drive, memory card and CD/DVD keeps data for future use and is not the CPU's direct working memory.

8. 8

   A file system organizes stored data as files, folders and paths and supports create, open, save, copy, move, rename, search and delete operations.

9. 9

   One byte = 8 bits and one nibble = 4 bits; school-level storage units commonly use 1 KB = 1024 bytes, 1 MB = 1024 KB, 1 GB = 1024 MB and 1 TB = 1024 GB.

10. 10

    For number systems, binary uses base 2, octal uses base 8, decimal uses base 10 and hexadecimal uses base 16 with A to F representing 10 to 15.