Device for checking for continuity. It reacts to a resistance below ~100ohm, normally acoustically; some devices have a selectable threshold. Usually part of a multimeter.

Alternating Current. In a time/voltage diagram, AC voltage represents a sine function (usually), or just any periodically alternating function. The mains voltage is AC voltage, for example.

Normally, signals are active high, which means a voltage level of 0V represents a logical 0 (LOW) and a voltage of above 5V represents a logical 1 (HIGH). If, for example, an IC pin is named "CS" (chip select), the chip is usually selected by pulling this line to HIGH (5V for TTL), and it gets deselected by pulling it to LOW (0V).

Analog-Digital Converter.

Device for measuring electric current. Usually part of a multi meter.

Logical function which is TRUE if all inputs are TRUE. A B | A AND B -----+------- 0 0 | 0 0 1 | 0 1 0 | 0 1 1 | 1 Examples: 7408: 4 AND gates with 2 inputs each 7409: 4 AND gates with 2 inputs each, open collector 4081: 4 CMOS AND gates with 2 inputs each

Ball Grid Array. A type of chip package where the fixing method consists of a number of solder balls mounted under the chip and directly soldered onto a PCB.

Board made of pertinax or other insulating material for building prototype circuits. It contains a matrix of holes. There are also types with soldering pads around the holes, these cost more but are easier to work with.

Same as driver.

The name for a set of lines/signals fulfilling a common function, for example, the address bus and the data bus. Examples include the PCI bus, H.100 and H.110 buses