What's the difference between IP forwarding via /etc/sysctl.conf and /proc/sys/net/ipv4/ip_forward?

Question

I've only used /proc/sys/net/ipv4/ip_forward to enable/disable IP forwarding so far. However, I recently came across a video where the author uses /etc/sysctl.conf to enable IP forwarding. Did he do that so that the modification survives reboots?

Answer 1

It turns out it was true - Writing to sysctl.conf allows for permanent changes. Source - https://www.cyberciti.biz/faq/making-changes-to-proc-filesystem-permanently/