The interface here was `wlp3s0`. It starts with 'w', so it's a wifi card. Each internet adapter has a name, called a 'MAC address' in order to identify itself to outsiders. The first three parts of a MAC address are given by the manufacturer (like a family name), and the rest are just for that one device.
The '192.168.0.1' address ends in '.1', so it's probably a router. The manufacturer is 'Technicolor' (`arp-scan` has identified this from the first digits of the MAC: '0c:02:27').
Next is 192.168.0.15, which is labelled as a 'raspberry pi'. Finally, the '.10' address is a mobille phone.
Mac addresses are easy to fake, so don't trust this output to keep you safe.
The `-F` means 'do this fast, by only scanning normal traffic' (ports below 1000).
```
Starting Nmap 7.80 ( https://nmap.org ) at 2020-01-09 13:52 CET
Nmap scan report for 192.168.0.1
Host is up (0.011s latency).
Not shown: 99 closed ports
PORT STATE SERVICE
80/tcp open http
MAC Address: 0C:02:27:BC:AA:A1 (Technicolor CH USA)
Nmap scan report for 192.168.0.10
Host is up (0.0040s latency).
All 100 scanned ports on 192.168.0.10 are closed
MAC Address: DC:0B:34:94:7C:C4 (LG Electronics (Mobile Communications))
Nmap scan report for belgradecats (192.168.0.15)
Host is up (0.0096s latency).
Not shown: 98 closed ports
PORT STATE SERVICE
22/tcp open ssh
53/tcp open domain
MAC Address: B8:27:EB:4A:CD:D9 (Raspberry Pi Foundation)
Nmap scan report for 192.168.0.13
Host is up (0.0000080s latency).
Not shown: 99 closed ports
PORT STATE SERVICE
22/tcp open ssh
Nmap done: 256 IP addresses (4 hosts up) scanned in 5.34 seconds
```
Network traffic is split into different types of information. Each one gets a number called a 'port'. Most of this information is dead, so only a few ports are used nowadays.
The first one shows port 80, so you can visit it on a web browser. The next shows 53 (so it's handing out names of local computers) and 22 (so you can access it via ssh).
You can scan outside addresses with:
> sudo nmap facebook.com
However, when you scan something, that machine will see you, and you may set off alerts, which then have to bother whoever's looking after that address.
So if you want to try out nmap from outside, find a place you have permission to scan (like your own external IP address), or try:
