Do you want to share files (copy, move, rename, delete, create directory) between two laptops? Do you need the fastest way? When there are only two laptops, it is slow if you must config Samba first. Instead, you can just use SFTP over a wifi hotspot to copy or move data from one to another laptop. You can do it all via Nautilus or another GUI file manager. It is easy to do. The requirement is just openssh-server installed in one laptop. I use Ubuntu as client and Blankon as server in this example.
What we will do is remote login via SFTP from one laptop into another laptop. We will login with server current user. SFTP is a Secure FTP protocol. With SFTP, you can do any FTP stuff securely. You need openssh-server package in Ubuntu to do it. And because of SFTP, you can do this via file manager. In this guide, I use Dolphin as file manager. You may use Nautilus, Thunar, Caja, Nemo, or PCManFM. Of course, you may use Filezilla too.
Connect The Laptops via WLAN
Either laptop should create a WLAN (wifi hotspot) and another one connect to that WLAN. Or, you can just connect those laptops into a WLAN from a router. You must aware that the router must be yours (so it is safe) and allows laptops to interconnect (because some public router forbid it).
Install openssh-server into a laptop and you may let the other. We assume that the laptop has openssh-server is a server and the other one is client. But of course you may install openssh-server in both laptops so they can login reciprocally into each other. The command is:
sudo apt-get install openssh-server
From the client laptop, do a SFTP login into the server laptop. To do that, open your file manager > Ctrl+L > type the URL sftp://192.168.1.3 (change it with the server IP) > press Enter > press OK if a dialog asks to continue > enter the username and password from the destination user from the server > your file manager now logged into the server laptop.
If You Don't Know The IP
You can use ifconfig command in server to know the IP address. You can also see the IP address by opening your Network Manager.
By using same technique, in Virtualbox, we can also connect guest OS into host OS. We can do it as long as the host have openssh-server. In this case, I use Ubuntu as host and Linux Mint as guest.