Data

Data, information and knowledge

Data needs to be part of a structure like a sentence in order to give them meaning.

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

These are two ways to check that data entered into a computer is correct.

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

Is about keeping data safe. Data could be:

* 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

Rapid data transfer: files can be shared quickly and easily around the globe using the internet. Files could be:

* emailed as an attachment

* sent over instant messenger

* downloaded from a website

* accessed over a private network


Keywords

Bandwidth: amount of data that can be streamed over a given time.

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.