PS: Here we are talking about AVR Micro controllers by Atmel, Please do not confuse it with Automatic Voltage regulator or something else.
What is the full name of AVR ?? What does AVR stands for ? AVR stands for nothing its just a 3 letter word just like PIC. Though some people name it as “Advanced Virtual RISC” but Atmel itself does not claim any official meaning of the word AVR. Anyways who cares as long as it suits our purpose
Well, not any kind of heavy definition. AVR is a Microcontroller architecture by Atmel, very popular among hobbyist
They are RISC devices. RISC stands for “reduced instruction set computing” and means that the devices are designed to run very fast through the use of a reduced numbers of machine level instructions.
This reduced number of instructions contributes to the speed due to the fact that, with a limited numbers of machine instructions, most can run in a single cycle of processor clock.
All the above statements means AVR processor using an 8MHz clock can execute nearly 8 million instructions per second, a speed of nearly 8 MIPS.
As said earlier AVR is first of all a microcontroller. So it has internal Memory, I/O ports and many other peripherals.
The memory section of the Atmel RISC avr processor is based on the Harvard modal, in which various portions of the memory are seperated to allow faster access and increased capacity. The CPU has a separate interface for the FLASH code memory section, the data memory section, and the EEPROM section, if one is present.
AVR is very rich in On chip peripherals. They have almost all the features required in a modern days microcontroller.
To learn more about Rich features of AVR read some initial pages from Datasheet of ATMega16.