Hi Cortez,
linkedTo option makes the axis inherit extremes (min and max) from master axis. Please see the y axis values in those two examples:
- without linkedTo:
https://jsfiddle.net/BlackLabel/dkes1ogb/
- with linkedTo:
https://jsfiddle.net/BlackLabel/6ah4k3fc/
API reference:
https://api.highcharts.com/highcharts/yAxis.linkedTo
When it comes to yAxis property, it allows you to define to which axis series should be assigned and is particularly useful when you have multiple series that require different scales or in order to increase chart readability:
https://api.highcharts.com/highcharts/series.line.yAxis
Additionally, ticks and extremes (if not set in axis config) are calculated based series values, so assigning series with yAxis property to specific axis, will have indirect impact on those calculations.
Now when when it comes to those two properties and alignTicks. Extremes are set in the following order of importance:
linkedTo >
axis config (min and max) >
alignTicks >
series data. Ticks calculations are more complex and it is hard to clearly tell the outcome as it heavily depends on the data and as I said before, alignTicks interfere with tickInterval value.
Feel free to ask any further questions.
Regards!