ICT Unit 2 (Revision Guide)
Benefits of encoding data - correct answer-Less memory is used
It is faster to enter the data when you know the codes
Fewer errors are made when entering the data
Validation is easier because there is a fixed set of codes
Benefits of keeping data in a digital format - correct answer-Less physical space is needed
for file cabinets and sheets of paper
Data is more secure
Data can be easily backed up and duplicated
Data can be encrypted so that if it gets into the hands of the wrong people, they wont be
able to access it.
Data can be easily edited
Data can easily be transmitted to another device
Drawbacks of keeping data in a digital format - correct answer-Equipment can be expensive
Specialist staff are required or current staff need training
Viruses/hackers may damage or destroy that data
Equipment failure may damage or destroy data
Verification methods - correct answer-Visual check
Double keying
Parity check
Explain double keying - correct answer-Double keying is when 2 people enter the data, the
computer compares the data and if it is identical, the data is accepted, if not, the data is
rejected and an error message is displayed.
Explain a parity check - correct answer-A parity check is when a number is added on to the
end of the information that is being transmitted. As data is transmitted in binary, the extra
digit will be 0 if there are more 1s in the sequence and 1 if there are more 0s in the
sequence.
Data validation methods - correct answer-Range check
Presence check
Format check
Check digit
Batch total
Hash total
Explain the term batch total - correct answer-A batch total is a data validation method
whereby a number is calculated at the start of the data transmission and at the end, the
same calculation is performed, if the number is different then an error has been made in
transmission.
Benefits of encoding data - correct answer-Less memory is used
It is faster to enter the data when you know the codes
Fewer errors are made when entering the data
Validation is easier because there is a fixed set of codes
Benefits of keeping data in a digital format - correct answer-Less physical space is needed
for file cabinets and sheets of paper
Data is more secure
Data can be easily backed up and duplicated
Data can be encrypted so that if it gets into the hands of the wrong people, they wont be
able to access it.
Data can be easily edited
Data can easily be transmitted to another device
Drawbacks of keeping data in a digital format - correct answer-Equipment can be expensive
Specialist staff are required or current staff need training
Viruses/hackers may damage or destroy that data
Equipment failure may damage or destroy data
Verification methods - correct answer-Visual check
Double keying
Parity check
Explain double keying - correct answer-Double keying is when 2 people enter the data, the
computer compares the data and if it is identical, the data is accepted, if not, the data is
rejected and an error message is displayed.
Explain a parity check - correct answer-A parity check is when a number is added on to the
end of the information that is being transmitted. As data is transmitted in binary, the extra
digit will be 0 if there are more 1s in the sequence and 1 if there are more 0s in the
sequence.
Data validation methods - correct answer-Range check
Presence check
Format check
Check digit
Batch total
Hash total
Explain the term batch total - correct answer-A batch total is a data validation method
whereby a number is calculated at the start of the data transmission and at the end, the
same calculation is performed, if the number is different then an error has been made in
transmission.
