| 🌐 What is an IP address? | A unique identifier for devices on a network |
| 📡 IPv4 vs IPv6 | IPv4: 32-bit (e.g., 192.168.1.1) | IPv6: 128-bit, 8 groups |
| 🏢 Public vs Private | Public: internet-routable | Private: local networks (192.168.x.x, 10.x.x.x) |
| 🔍 Geolocation | IPs can reveal approximate location (city/country) |
| Class A | 1.0.0.0 - 126.255.255.255 | Large networks |
| Class B | 128.0.0.0 - 191.255.255.255 | Medium networks |
| Class C | 192.0.0.0 - 223.255.255.255 | Small networks |
| Multicast | 224.0.0.0 - 239.255.255.255 |
| Reserved | 240.0.0.0 - 255.255.255.255 |
| Class A Private | 10.0.0.0 - 10.255.255.255 |
| Class B Private | 172.16.0.0 - 172.31.255.255 |
| Class C Private | 192.168.0.0 - 192.168.255.255 |
| Localhost | 127.0.0.0 - 127.255.255.255 |
| Link-local | 169.254.0.0 - 169.254.255.255 |
| 🔒 Use VPN | Encrypts traffic and hides your IP |
| 🛡️ Firewall | Blocks unauthorized access |
| 📡 Check IP reputation | Some IPs are flagged for spam/malware |
| 🌍 Avoid public Wi-Fi | Unless using VPN, data can be intercepted |