What Are Sprinkler Timers?
Sprinkler Timers (sometimes called controllers) are devices that are used to control sprinkler systems. THey control when and how often individual sprinkler zones in a sprinkler system should come on. Older timers are electronic, and can have complicated push-button interfaces. Newer "Smart" timers can be controlled via a smartphone using a Wifi connection or Bluetooth. Some of these newer timers, such as the B-Hyve from Orbit do not have a user interface on the unit itself, and require a device such as a phone or tablet in order for a user to interface with the timer.
Most timers operate using off-the-wall power as an input (120v in the U.S.A.). The signal sent out is usually an alternating current (A.C.) 24v signal. This signal opens up the solenoid on the other end of the wires.
Different Types of Sprinkler Timers
Most brands of sprinklers also manufacture and sell sprinkler timers. The timers that are most common right now are older electronic timers with button interfaces.

As well as smart timers, with phone and device interfaces. These two types of timers make up the vast majority of sprinkler timers in systems. Sometimes, there can be older, more mechanical control boxes that have to be activated manually by hand in order to turn a zone on or off. But nowadays these are quite rare to come across, and should be upgraded to an electrical system for ease of use and maintenance.

How to Program Sprinkler Timers
Sprinkler timers vary widely in how programming should be done. In short, you should consult your owner's manual to learn how to program your specific timer. In many areas, there is also a mandatory water restriction in place due to drought. Utah, for example, follows the Slow the Flow initaitive. Most of the time, local watering guidance and restrictions should give you a fairly good idea of how often and how much you should water your lawns.
The amount you water your plants and lawn also depends on a few factors, such as soil type, slope of your landscaping, shade, percentage of rainfall that reaches the area, and a few others. That is one of the biggest advantages to having a system with a smart timer, as they automatically calculate how often you should water, and tell you those recommendations. If you don't have a smart timer in your system, we recommend calling your local experts to help you upgrade to a smart timer. These smart timers will also automatically do a rain delay, further increasing your water efficiency and grass watering, all without any input from you.
If you're still using an older button or dial interfaced timer, programming your systems to run on an A/B cycle will help keep things separate. Make sure to monitor how green your grass is staying, and watch for excess runoff coming off your lawn. Ultimately you can change your watering to perfectly match your lawn's needs.
On older timers that don't have a "smart water" system, make sure you do a rain delay as well. This helps prevent overwatering, and should be done every time there's rain in the foreccast, and in some cases even when there is just high humidity.