Most of you know what I'm talking about when you read the word "downtime", and I'm sure that a monitoring service tool is something very familiar when it comes to a webmaster. There are many freee and paid monitoring tools that you can use to keep your website safe from downtimes, bugs, or anything else that can hurt your website or business online.
Now understand one thing, these tools are not going to prevent your server from going down, their function it's just only to notify you in real time if your server goes down.
Most of hosting providers these days are offering those tools for free, for example namecheap offer something similar, their tool it's pretty basic but it still can help you a lot if you are worried about if your website is always online.
What I like from these tools is that, well everything is automated so whenever your website goes down you'll receive reports immediately to your email, or even via sms to your cell phone, of course that depends on the monitoring tool if they offer these features for free or paid version only.