This device can capture typewritten characters or handwritten characters that are of standard size and without stylish loops.
Optical Mark Reader (OMR)
OMRs are connected to the computer to capture pencil marks. It is used in marking objectives answers that are marked with a soft pencil (2B pencil). it is used in WAEC, JAMB etc. for marking objectives answers.
Bar Code Reader
This device is commonly used in point of scale terminal. This is used only when the articles for sale are marked with bar-codes ( Binary combinations of thick and thin vertical black bars). This bar-code may contain stock number and price (sales data). The bar-code Reader captures sales data to the computer for processing. This devices is also used in the Libraries.
The Central Processing Unit: (CPU)
The central processing unit is the brain or the heart of a computer system that processes data. In fact it is the computer itself while other units like input, output and storage units are referred to as the peripherals. The CPU must be linked with either cables or communication lines to all the peripherals that build up the components of the entire computer. The CPU consists of three sub sections. Namely:
The Main Memory: The main memory comprises the ROM and RAM. The ROM which is the Read Only Memory holds manufacturer's software while the RAM holds information that comes from the secondary storage or ROM during execution. In reverse, it moves information from CPU to the secondary storage. When the computer power is turned off, information or programs on the Ram wiped up. So, data held by the RAM is not permanent. The information in the ROM is permanent even when then computer power is turned off.
