How to use a laptop as a second monitor 
                     HOW TO USE A LAPTOP AS 
A SECOND MONITOR
Introduction:
 There are various ways to use a 
laptop as an additional monitor 
for another computer, 
depending on the hardware and 
operating system.
Source: border.pakasak.com 
Verify Hardware Compatibility:
  Make sure the laptop you plan to 
use as a second monitor has the 
required ports, as does your main 
computer.
  Which is the one you want to use 
as your primary machine. Usually, 
this would require a USB-C, 
DisplayPort, or HDMI port on each 
device.
             Source: pexel.com
Verify Software and Connectivity:
  Some laptop operating systems 
come with built-in software that 
allows you to use it as an external 
monitor.
  In other cases, you may need to 
purchase additional software. 
 Make sure the two devices have 
compatible ports for a direct 
connection or are linked to the 
same network.
Source: vssmonitoring.com 
Determine the Ports: 
 Determine which ports are open on 
each device. 
 For example, connecting laptops as 
second monitors is more common 
with HDMI and USB-C.
             Source: pinterst.com
Use HDMI or DisplayPort:
  You can connect two devices 
directly with a compatible cable if 
they both have an HDMI or 
DisplayPort. 
 Navigate to the display settings on 
the main computer and select the 
option to extend the display to the 
second monitor.
S            ource: reddit.com
Software Solutions:
  You can use a laptop as a wireless 
second monitor by using certain 
software solutions. For this reason, 
apps like "Twomon" and "Duet 
Display" are made. 
 Use the instructions to connect and 
use the laptop as an extra display 
after installing the app on both 
devices.
Source: reddit.com
Network-Based Solutions: 
 You can also extend your display 
using your home network with 
certain software.
  This functionality is made possible 
by programs like "SpaceDesk" and 
"Splashtop Wired XDisplay". 
 Set up and install the necessary 
software on both devices.
                 Source: facebook.com 
Verify the Display Settings: 
 Navigate to System Preferences > 
Displays (Mac) or Display Settings 
(Windows) on your primary 
computer.
  Options to identify and set up the 
extra display should be visible. 
 Make sure the display extends or is 
mirrored in accordance with your 
preferences.
Source: amazon.com
Modify Resolution and Orientation:
  After connecting, you may need to 
change the secondary display's 
resolution or orientation to suit 
your needs.
  These settings are typically located 
in the display settings of the 
operating system on your primary 
computer.
Source: reddit.com 
Conclusion:
 Not every laptop can function as a 
second monitor, and the 
procedures can change based on 
the hardware and software being 
used. 
 For the most precise instructions, 
always consult the manuals that 
came with your device or operating 
system.
                       Source: reddit.com