EM4 Digital Electronics Practice Test 2026 – The Complete All-in-One Guide to Exam Success!

The NOT symbol represents negation in digital logic, so the device is called an inverter. A NOT gate inverts the input: if the input is 0, the output becomes 1, and if the input is 1, the output becomes 0. In diagrams, this inversion is shown with a bubble at the output of the symbol, signaling the negation. A buffer, by contrast, passes the input through unchanged (often with added drive strength), a transistor is a basic switching device used to build gates, and a latch is a memory element. Hence the inverter is the correct label for the NOT symbol.