Introduction to Signatures

What is a Signature?

You may think of your school’s internet filter as something that blocks and allows specific web addresses, but the truth is a bit more complex than that. It actually blocks and allows Signatures. Signatures can contain websites, applications, games, search keywords, IP addresses, ports and groups of websites.

These are the types of Signatures you’re most likely to see when managing your class:

  • Website signatures

  • Group signatures

  • Category signatures

  • Game signatures

Website Signatures

In Classwize, Website Signatures usually refer to domains and subdomains, not individual URLs (links). 

This means that if you make a rule using a Website Signature,  it will apply to all of the individual pages in that website.  

For example, setting an Allow rule for the Google Signature will let the students access images.google.com, docs.google.com, drive.google.com and similar pages. Blocking the Google Website Signature will stop students from accessing any Google page.

Why don’t Rules apply to individual URLs?

We don’t usually have Signatures that are URLs  because we can't always see and filter full URLs before the page reaches the student.

Group Signatures

Most websites need other websites in order to work properly. Usually with very popular websites, we’ll create one Signature that includes both the website and all of the other websites it needs to work. We call these Group Signatures.  Group Signatures let you create an Allow rule on a site without worrying that some of its components will not work.

For example, if you Allow Khan Academy but Block YouTube content, Khan Academy won’t work properly for your students. Because of this we include YouTube in the Khan Academy Group Signature, so that videos will still load if you Allow Khan Academy but forget to Allow YouTube.


In this example, Khan Academy is allowed and will show Youtube videos.

Category Signatures

The internet is enormous, and we can’t expect you or your school’s IT team to set a rule for every website and service.  Instead, we classify each website into one or more Categories and let you create rules that apply to every single website in that Category. 

For example, websites such as Facebook, Twitter and Twitch all belong in the Social Media category. By blocking (or allowing) access to Social Media, you can manage your students’ access to all sites and apps that belong in this category.

Parent and Child Categories

Categories can also contain other categories.  These are called Parent and Child categories.  For example, a very broad parent category called Entertainment contains several child categories:Animation and Manga, Celebrities and Entertainment, Music and Audio, Sports, and Streaming Media.  Each of these child categories also contain Signatures.  

You can set rules on Parent and Child categories, as well as individual Signatures. This gives you and your school a lot of flexibility in how you make and apply rules.  You can create a rule that applies to the parent category, and then create exceptions to that rule by applying a different rule to a child category or an individual signature.

Game Signatures

We’re not saying it’s hard to stop kids from playing Among Us, but… it’s hard to stop kids from playing Among Us. Or Fortnite, or Roblox or whatever other game is the current flavor of the month.  There are often multiple ways to access these games, and so we create specialized Game Signatures that let you Block—or Allow— those games everywhere they can be played.