My brother-in-law called about a bail hearing and I had no idea how to explain sureties

https://kyledonmillsbloom.huicopper.com/charged-with-domestic-assault-in-toronto-the-critical-hours-after-arrest

My brother-in-law sent a message about a bail hearing and I had no idea how to explain sureties, we panicked through questions until a friend finally found info online.