Data
Data, information and knowledge
Information is when data has been put into context. (like in a sentence).
Knowledge is the ability to understand information and then from judgments, make decisions and predictions based on that understanding.
Data leads to information, and information leads to knowledge.
Data validation and verification
Validation is an automatic computer check to ensure that data entered is sensible and reasonable. It does not check the accuracy.
Verification is performed to ensure that data entered exactly matches the original. There are two main types:
- Double entry - entering the data twice and then comparing the two copies.
- Proof reading data - involves someone checking the data.
Both of these methods take a lot of time and can be costly.
Data security
* lost or damaged due to a system crash.
* corrupted as a result of equipment failure.
* lost by accidentally deleting or overwriting files.
* lost or corrupted by computer viruses
* hacked into by unauthorized users.
* destroyed by natural disasters.
To keep data secure you could:
*make regular backups of files.
* use anti virus software to protect files.
* use a system of passwords so that access is restricted.
* use data encryption techniques to code data so it makes no apparent sense.
Data transfer
* emailed as an attachment
* sent over instant messenger
* downloaded from a website
* accessed over a private network
Keywords
Latency: is the delay between data transfers.
Buffering: when something you are streaming over the internet has to stop and load. For example the little buffering circle on YouTube videos.