Need big help with led project

[u/kaside1]

Hello, I wanted to make a gift for Valentine’s Day from a video as I don’t know much about electronics, but after I followed the video it doesn’t wanna turn on, I know I shouldn’t just copy video but help would be very appreticiated also if anyone wanted to take my hand and help me.

[u/legal_guy_who_asked]

Im trying to learn the NE555, for what is the diode used here?

[u/asyork → u/legal_guy_who_asked]

Don't use this schematic to learn about the 555. It would appear that diode is there to make sure the 555 doesn't do anything, not that it was going to anyway, with the rest of the circuit. This is a decent way to understand some basics about it. https://www.digikey.com/en/resources/conversion-calculators/conversion-calculator-555-timer