Hardware & Software Logic Gates PC components and what they do (CPU, GPU, RAM, ROM etc) CPU (Central processing unit): central processor where most calculations take place GPU(Graphics processing unit): a programmable logic chip specialized for display function V RAM(Random access memory): volatile, it will forget when powered off; faster than hard drives or SSD V ROM(Read only memory): non-volatile, which means it keeps its contents regardless of whether or not it has power PC Connectors & Ports and what they do (DIV VGA USB etc) V USB (Universal Serial Bus): high speed port PS/2 : use for keyboard and mouse V Ethernet: Access internet; other network device/ other computers V DVI/HDMI: connect PC to a monitor or TV/ HDMI can carry sound Display: supports higher than HDMI PCI Express (PCIe): Peripheral Component Interconnect Express/Very fast SATA: uses to connect Hard Drives and SSDs to the motherboard V M.2 connector: connect SSD to motherboard/ uses PCIe/SATA for data transmission What a CPU register is Special memory cells that are used as temporary holding places V Similar to RAM but faster ASCII & Unicode V ASCII (American Standard code for information interchange): 1 byte per character V Unicode simply defines a number for each character. The way its stored in a file called encoding. There are 2 main encoding: - UFT-1fi use 2 bytes per character - UFT-8 use 1 byte if possible, if not use multiple bytes. It is also backwards compatible with older systems Types of data storage and how they work (Hard Drives, Solid Sate drives, optcal drives) V Hard Drives: - Spinning metal disks store data by encoding magnetic fields into the surface - High storage density - Low cost - Slow Solid State Drives: Fast/Expensive Optical(DVDs): uses laser to read and write data to a plastic disk/ Slow/ Low storage density What a number base is (binary, decimal hexadecimal) V Binary is a base 2 number system 0 and 1 V decimal hexadecimal is a base 1fi number system "The basic concept of how an image is store on a computer. V Computer screen has millions pixels, each pixel has 3 colours: red, green and blue. A computer is able to show images by varying the brightness of each sub pixel Diferent data types V Integers (int): whole number/ 4 bytes long V Character (char): individual character/ 1 byte long String: collection of characters (list of char)
V Float: Numbers that has decimal places / 4 bytes long V Double: same as float but can stored number with more precision/ 8 bytes long What a CPU instructon is. Control unit: read instruction and determines how to execute V Arithmetic/Logic unit (ALU): Registers: memory cells V Cache: high speed storage area for holding data. The basics of fle compression/what makes some fles more compressible than others. V Lossless compression: the file can be compressed into a smaller file and the later decompressed back into the original with no loss of data V Lossy compression: file is compressed