Type: Monostable, Astable, and Bistable multivibrator.
Pins: 8-pin Dual In-Line Package (DIP), also available in surface-mount packages (SMD).
Supply Voltage (Vcc): 4.5V to 15V (some variants up to 18V).
Operating Temperature Range: -55°C to +125°C (Industrial grade).
Output Drive Capability: Can drive loads up to 200mA (standard NE555) or 200mA (high output current versions).
Pin Configuration:
Pin 1 (Ground): Connects to the ground.
Pin 2 (Trigger): The input for initiating a timing cycle (used in monostable mode).
Pin 3 (Output): The output of the timer, typically connected to a load.
Pin 4 (Reset): Active low reset pin (to disable the timer).
Pin 5 (Control Voltage): External voltage control for adjusting threshold and trigger levels.
Pin 6 (Threshold): Input that monitors the voltage at the capacitor in astable or monostable configurations.
Pin 7 (Discharge): Discharges the timing capacitor in astable or monostable modes.
Pin 8 (Vcc): Connects to the positive supply voltage.
Timing Characteristics:
Monostable Mode: The output is high for a fixed time determined by an external resistor (R) and capacitor (C). The formula is: t=1.1⋅R⋅Ct = 1.1 \cdot R \cdot Ct=1.1⋅R⋅C 
Astable Mode: The NE555 continuously generates a square wave with adjustable frequency and duty cycle. The frequency and duty cycle are controlled by external resistors and capacitors