A good starting point to explaining reducers is that you are reducing two things into one.
A redux reducer:
The action and the current state reduce into the new state.
And of course it doesn't matter how many reducers or combined reducers your state uses - they're all ultimately just doing this.
This also works for Array.prototype.reduce(). You're reducing two things into one.
Allow me, however, to go one step further. You're 'working' class. You're not 'lower' than anybody else.