Data Collection

Data Capture This is the first stage involved in getting data into a computer Various input devices are used when getting data to the computer It is the process by which the computer acquires data from the user

Data Capture There are two main ways of inputting data into a computer: Manual data input Automatic data input/data capture

Manual data input Data is entered directly into the computer This is done one transaction at a time by hand The various input devices are used in order to enter the data This data input method can be long and tedious

Automatic data input Data is entered directly into the computer from source documents This method is considered faster and more efficient

Source documents These are pieces of material (documents) on which data is first recorded before it is entered into the computer Data is captured from the source and then transferred directly to the memory of the computer for processing

Source Documents Examples of sources documents are barcodes

Data Input Data captured or entered manually must be checked in order to cut down on errors made by users Data captured or entered must be verified and validated before it is processed and placed in storage

Data Verification It is a process whereby the data is checked for accuracy and inconsistencies after data entry is done This is to ensure there was accurate transcription or copying of the data

Data Verification In order to verify data the user may be asked to enter the same data twice. Data typed in the second time is compared with the same data already entered to determine a correct match If a difference in the two entries is found, the data is deemed as containing an error

Data Verification Example: being asked to enter your password twice

Data Validation Once data has been entered into the computer by the user, it is checked to ensure it obeys the rules which apply to it This process of checking is called data validation Data validation is the process of ensuring that a program operates on clean, correct and useful data

Data Validation Example: (1) being asked to enter your birthday according to the format – mm.dd.yy (2) Checks fields to ensure data in these fields corresponds, e.g., If Title = "Mr.", then Gender = "M".

Exercise 1. How are source documents used in the process of data capturing? 2. What is the difference between data verification and data validation? Why are these processes important for the proper functioning of computers?