Things that were brushed past

RFID chip

Radio frequency identification chip: used for tracking inventory, health data and livestock

Pros:

Does not require line of sight like barcodes, multiple can be read at once, durable

OLED vs LCD monitors

OLEDs are brighter, thinner, lighter, each pixel provides own illumination (so can be switched off to achieve true black with no glow) and made of plastic rather than glass. LCD is cheaper and is backlit using LEDs.

Check digit

Last digit of barcode. Algorithm applied to other digits and if result is not the check digit, then there is an error

Run length encoding

3W6B3W etc.

Binary shifts

Left shift:

One left shift doubles, two left shifts quadruple
msb moved into the carry bit, zero occupies lsb

Right shift:

One right shift halves, two divides by four

lsb moves to carry bit, zero comes in the left as the new msb

Disk thrashing

Consequence of pages being swapped between hard disk and main memory too often. Causes the computer to freeze.

PAN

Personal area network. Spans a couple of metres.

Mostly uses bluetooth or USBs, but can be wired.

Modem

Connects network to an ISP. (whereas router connects networks together)

Bus topology

All devices connected to one main cable (can use cables to connect to it).

Data can only be transmitted in one direction at a time.

Heavy usage can cause cable to degrade.

Dependent on main cable.

Easy to add nodes.

Circumvent

Editing/viewing code to bypass validation. Done in client side processing. This is why password checking or data validation should be handled on the server side too.

API

Application programming interface. A connection between computers or between computer programs. Has an API specification which is set a of rules and protocols that enables this communication.

Paradigms

Different approaches to using a programming language to solve a problem. Imperative or declarative.

Imperative paradigms

Code that clearly specifies the actions to be performed.

Procedural:

Sequence of instructions. May be contained within procedures (like a function but no value is returned, you use them all the time). e.g. Python, Pascal

OOPs:

Uses classes made of attributes and methods. e.g. Python, Java

Declarative paradigms

States the desired result rather than the exact series of instructions that need to be performed to get to the result.

Functional:

Built by reusing a set of functions, e.g. C#, Java

Logic:

Uses a knowledge base, patterns and logic to produce a result. AI and machine learning.

Enumeration

A complete, ordered listing of all the items in a collection

Static linking

Libraries combined with code after they are compiled (separately) to form one big executable file

Pros:

• Allows separate compilation of programmer’s code and libraries

Cons:

• Every program must have its own copy of the library rather than the programs sharing one copy of the library

• Library makes file larger which is unnecessary if program doesn’t even make use of the library

• Must recompile if you want to get any updates that have been made to the libraries

Dynamic linking

Libraries linked at runtime. Code has one function statically linked which allows a link library to be accessed when the program starts. The link library determines which external libraries the program will need.

Pros:

• Allows separate compilation of programmer’s code and libraries

• Smaller file size

• If libraries are updated, no need to recompile to reap the benefits

Cons:

• Slightly slower program startup

• Must have libraries on hand

Loader

Moves executable file into main memory so they can be run by operating system