The easiest way, is by simply looking at the ports on your computer.
If you are not sure, please check your computer or smart device's manual or contact the manufacturer directly.
Below you will find a few examples of ports commonly available on computers and smart devices:
USB-C
USB comes in many specifications. Some ports will only support charging while other will support data, video signal and even power delivery (meaning you also get power on your device). In some situations, it may be referred to as "Thunderbolt 3 or 4" or simply "Thunderbolt"
Please check with your device's manufacturer for the exact specifications.
Standard USB-C
Could be just for charging devices or for data and video transmission as well. If there are no identifying icons around, please check with the manufacturer.
USB-C Power delivery
If your USB-C port has a logo similar to this, then it should support Power Delivery but might not support video transmission.
USB-C DisplayPort Alt mode
If your USB-C port has a logo like this, then it supports DisplayPort Alternate Mode. This this port can both send and receive a video signal.
USB-C Thunderbolt (or Thunderbolt 3 / 4)
Capable of video and data transmission. Might also be able to handle Power Delivery. Check with the manufacturer for exact specifications
HDMI
For video and audio transmission. There are also different types with different transfer speeds.
For example, to get 4k video at 120Hz on Cintiq Pro 27, you will need HDMI 2.1 support.
DisplayPort and Mini DisplayPort (also known as Thunderbolt 2)
For video and audio transmission. Similar to HDMI.
DisplayPort
Mini DisplayPort / Thunderbolt 2
USB (or USB-A)
Most common connection although it is slowly being in the industry replaced by USB-C format
USB Standard (or 2.0)
USB 3.0
Supports higher transfer speeds. Usually identified by the blue pin tab.
Micro USB
Mostly for charging devices. Being replaced by standard USB-C in more modern devices