This circuit based project demonstrates the working of 555 timer in astable mode to generate pulses of time period 0.5 second. This pulse can be further used [[wysiwyg_imageupload::]]for anything where we need a pulse such as to blink a LED or to create fashionable blinking lights. This circuit of this project makes the use of timer IC NE555 which produces a constant square pulse of a desired frequency. This pulse could be either triggered or could be produced continuously depending upon the mode of 555 we are using. The two mostly used modes of 555 are Monostable and Astable. Here it is used in the astable mode with time period of half second, with high time period of 0.333 seconds and low time period of 0.166 seconds. Keep on reading to find out how the circuit is constructed and in what mode does the 555 IC works.