# Tick proc (world)

Source: https://ref.dm-lang.org/world/proc/Tick
Added in BYOND 515.

### Format
> `Tick()`

### When
> Called during the server tick, after sleeping procs and queued commands, just before map information is sent to the clients.

### Default action
> None.

This proc allows you to do any updates just before map info is sent out. One possible use for this is to run a movement loop, or sync up any user interface input that might have arrived and deal with it all at once.

```dm /Tick/
world/Tick()
    for(var/client/C)
        if(C.mob?.move_dir)
            try
                step(C.mob, move_dir)
            catch
                // empty catch, just so a failed step won't break the loop
```

> [!note]
> 
> The tick will not wait if this proc sleeps. It effectively has [set waitfor=0](https://ref.dm-lang.org/proc/set/waitfor.md) already built in. It's a good idea not to sleep in this proc or any of its callees at all, since it will keep getting called every tick.

### See also
- [cpu var (world)](https://ref.dm-lang.org/world/var/cpu.md)
- [map_cpu var (world)](https://ref.dm-lang.org/world/var/map_cpu.md)
- [tick_usage var (world)](https://ref.dm-lang.org/world/var/tick_usage.md)