Oltromen Ripot has posted twice already with very good explanations. Perhaps examples will help
westlife. Do a traceroute and see which of the below is closest to yours.
This is private IP. (Digi mobile data) whatismyip: 115.164.213.14
CODE
% traceroute 8.8.8.8 | column -t
traceroute to 8.8.8.8 (8.8.8.8), 64 hops max, 52 byte packets
1 172.20.10.1 (172.20.10.1) 6.706 ms 4.672 ms 4.312 ms
2 10.138.138.118 (10.138.138.118) 30.352 ms 33.715 ms 30.086 ms
3 * * *
4 10.132.47.46 (10.132.47.46) 28.326 ms 23.017 ms 19.999 ms
5 172.21.20.207 (172.21.20.207) 20.419 ms 20.631 ms 24.763 ms
6 * * *
7 172.21.2.250 (172.21.2.250) 40.436 ms 29.309 ms 28.952 ms
8 72.14.221.20 (72.14.221.20) 31.236 ms 22.789 ms 36.976 ms
9 108.170.250.1 (108.170.250.1) 25.200 ms
108.170.249.225 (108.170.249.225) 23.252 ms
108.170.250.1 (108.170.250.1) 30.591 ms
10 72.14.234.85 (72.14.234.85) 31.066 ms
142.250.62.57 (142.250.62.57) 23.950 ms
72.14.234.85 (72.14.234.85) 31.160 ms
11 dns.google (8.8.8.8) 39.246 ms 28.082 ms 30.025 ms
This is public IP. (Unifi 800) whatismyip: 175.142.125.212 (see how this IP corresponds to #2 below)
CODE
% traceroute 8.8.8.8 | column -t
traceroute to 8.8.8.8 (8.8.8.8), 64 hops max, 52 byte packets
1 router.local (10.0.1.1) 2.362 ms 0.415 ms 0.354 ms
2 175.142.125.254 (175.142.125.254) 3.025 ms 2.334 ms 2.364 ms
3 10.55.49.3 (10.55.49.3) 3.680 ms
10.55.49.1 (10.55.49.1) 4.882 ms 3.439 ms
4 10.55.48.14 (10.55.48.14) 5.563 ms
10.55.48.200 (10.55.48.200) 4.809 ms
10.55.48.18 (10.55.48.18) 5.102 ms
5 72.14.214.196 (72.14.214.196) 6.143 ms
72.14.214.220 (72.14.214.220) 5.354 ms
72.14.204.208 (72.14.204.208) 6.075 ms
6 * * *
7 dns.google (8.8.8.8) 6.486 ms 4.652 ms 4.788 ms
* anything beginning with a 10 and 172.16 to 172.31 are private IPs.