If you use an Arduino or similar development board, chances are it comes with some sort of USB connection that you can just plug into and program via your computer. If, however, you’ve moved on to systems that need to be programmed using a separate in-system programmer (ISP or ICSP for in-circuit serial programmer), you’ll need to connect to solder pads on the board you’re using.
Or you could use pogo pins to do the job, allowing you to literally hold the connectors on your board. You could make this fixture yourself, or you could just buy one from Tindie. Seller FemToCow has one available here for 10 bucks ($9.99 plus shipping), which looks pretty good from the picture. And that’s all I can really tell you about the quality of this device.
On the other hand, the Mad Electron Engineering YouTube channel decided to do a review of it starting at 4:00 in the video seen below. It’s an interesting piece, going over why you might need one of these, and the fact that you can make one yourself that likely won’t be as good. Although the presenter is clear that he wasn’t paid to do an endorsement, at the end of the video he does say, “Thank you very much, I love it, it’s great.”
One couldn’t ask for a better review than that, and hopefully the video will help others see the benefit of this little guy. We love finding Tindie product reviews in the wild and hope to see more in the future!