Frequently Asked Question

Step One:  Open System Preferences (or System Settings) from the Apple menu in the top left:

Step Two: Click General on the left (if you have a menu on the left).  Then click Software Update.

Step Three:  Ignore the Upgrade Now button (unless you want to change OSes).   System updates are at the bottom of this screen behind a 'More Info' text block.

Next you can select which updates.. it's normal to see Safari updates here as well and those are also worth installing:

After clicking install now you'll often get terms & service to agree to.  Updates can take as little as 10 minutes but 30-40 minutes isn't unusual.  Safari updates are usually 5 minutes or less.