Google Analytics - Bot Filtering Option
Google recently added a new bot filtering tool that can be enabled by adjusting your "view settings" within your Analytics configuration.
Bots are essentially automated software programs that access your website. Many don't run Javascript on your site and so won't be captured but those that do can often lead to unexpected spikes in traffic or inflated traffic figures that can also skew engagement metrics (e.g. a large volume of traffic from a particular source with a 100% bounce rate).
Bear in mind that bots may access your site as you actually signed up to a service - for example to check site availability or to run an SEO audit of your site. With some detailed analysis it's usually possible to identify these but it can make analysis harder and if you miss something it's possible that your figures could be skewed artificially.
To enable this setting you need to go to your Admin settings and tick a box to exclude known bots.
According to Google:
Selecting this option will exclude all hits that come from bots and spiders on the IAB known bots and spiders list. The backend will exclude hits matching the User Agents named in the list as though they were subject to a profile filter. This will allow you to identify the real number of visitors that are coming to your site.
You'll need to check the tick box in each of the views you want to apply it to. Bear in mind that best practice is to always maintain one master profile with no filtering.