As mentioned in the beginning of this module - there are plenty of services and packages that you could add to your website.

How do you know when you need a service (and which service you should use)?

Typically, you start at a certain problem - e.g. "I want to display a map on my website".

Then, as a next step, you can search for something like "web dev show map on website" - and in the search results you should find websites of services that can help you or blog posts / forum discussions that point you at fitting services.

Common problems & services would be:

• I want to send email to users => Solution: You can use services like Mailchimp (there also are many others!). Searching for something like "send email api" should do the trick.

• I want to allow users to log in via Google / Facebook / Apple etc (i.e. "social login") => Solution: Search for something like "website add facebook login" => You will find various search results, amongst them the official documentation page provided by Facebook: https://developers.facebook.com/docs/facebook-login/

• I want to display a map on my website => See above => You will probably find the Google Maps API / service documentation, though there also are other provides (e.g. OpenStreetMap)

• I want to add Analytics to my website to see how my users behave, where they come from etc => Solution: Search for something like "website add analytics" => You will find various results, amongst them the Google Analytics website and documentation

Of course there is an infinite amount of possible scenarios, problems and services - but web search is your friend!

When it comes to using a service, you should always dive deeply into the official documentation provided by the service as that documentation describes in detail how you should use the service. Often, official documentation pages also contain useful examples.