# How-to

Industry: Core

Each page answers one question, shows the call, works one example through, and says which version of GMT produced the results.

| Question | Page |
| --- | --- |
| How do I add business days when the weekend is not Saturday and Sunday? | [Add business days](./add-business-days/) |
| How do I show one moment in another time zone? | [Convert a time between time zones](./convert-between-time-zones/) |
| How do I check whether a wall-clock time exists on a day the clocks change? | [Check whether a local time exists on a DST day](./check-local-time-exists/) |
| Which library handles time zones and DST, and what does each return for a time that does not exist? | [Time zones and DST in JavaScript: which date library handles them](./time-zones-and-dst-in-javascript/) |