Dupont housing, Dupont 2.54mm connector housings are used to make custom jumper cables for solderless breadboards or to go between male and female headers.
KEY FEATURES OF DUPONT 2.54MM CONNECTOR HOUSING:
Fits standard Dupont style 2.54mm male and female pins.
Dupont connectors are the ubiquitous connectors used for making solderless breadboard jumpers as they come in both male and female contacts that mate well with 2.54mm / 0.1″ standard male and female headers as well as solderless breadboard contacts.
Besides making custom jumpers, many items that are not solderless breadboard compatible can be made compatible by soldering wires to them and adding these connectors.
One nice feature is that the same housing can mount either male or female contacts making them flexible in their application. On multi-contact housings you can even mix contacts in the same housing in order to key it.
Another nice feature is the housings are also very easy to get contacts in and out of unlike most housings.  if you decide you want to change from individual jumpers to one that has a 3-pin housing for hooking up to a sensor for instance, you can easily pop the single housings off and pop a 3-pin housing on.
There is a plastic tab that locks the contact in place. If this tab is lifted slightly, the contact slides out. If contacts don’t want to stay in the housing, the plastic tab can usually be pressed down a bit to help lock the contact in place.
Notes: These are designed to work with a standard 0.1″ spacing. When using them in an adjacent line, it works best to have the latch portion of the connector visible (facing out) as that side is slightly wider than 0.1″.
Nice.