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The original 74 series are very old. They need a regulated 5V supply and use a lot of current.
A valid high input is +2.0V or more and a valid low input is +0.8V or less.
An output high is +2.4V or more and a low output is +0.4V or less.
The input floats high and needs a max of 1.6mA to force it low.
One logic circuit output can drive 10 inputs because its max low current is 16mA.
74LSxxxx uses less current.
74HCxxxx uses a supply from 2.0V to 6.0V and uses much less current.