GCSE ICT - Single Award
Until details, here's some revision...
Why network? There are a number of advantages:
Great, huh? The only trouble is the disadvantages:
It's important to remember these factors, naturally...
What do you need?
A server. This could be a file server, a print server, or a web server (usually for email). The server can be Peer-to-peer or a client server. It’s likely to be a client server network for a school because Peer-to-peer is used for less than 10 computers.
A way of connecting computers. The two main ways are with cables or with wireless -- sending info through microwaves. The three types of connecting through cables are: Ring Network, Star Network, Bus Network. The most reliable is the Star Network.
WAN and LAN
There are two types of networks, a WAN network and a LAN network.
WAN stands for Wide Area Network while LAN stands for Local Area Network. From that it's pretty obvious that WAN in huge ones located all around the world, e.g. the T-Mobile phone company and LAN is used in small businesses that are located in one building, such as the school from the Case Study.
And that's pretty much all you need to know on networks!
These are very nifty because they allow you to store a load of data, and sort it...
However before we go onto them, we need to know what data is...
Shock! Horror! A forumula and we're not in Maths? It's true:
Information = Data + Context (Meaning).
Before any data can be input into the computer, naturally it has to be collected. This process is called data collection and can happen in many different ways, such as questionnaires, forms, bills... The data can also be input instantly into the database, for example with online electronic forms for Internet shopping, or barcodes in shops.
But for any data to be input into the database, first you need to make the database. It's important to know the parts of a database. The 'headers' are known as fields, while each row of information on a particular item is a record.
"StudentID" is a field, while all the info about Barney is a record.
The good think about databases is you can set rules for when you input data, to try to stop errors occuring. This is known as validation. Simple ones are:
More complex ones require you setting real rules. Take the DoB field above. In most cases, you'll know the age range, and therefore you can set maximum and minimums. < means smaller than. > means greater than. This is called range checks.