Infrared is invisible radiant energy, electromagnetic radiation with longer wavelengths than those of visible light. Most of the thermal radiation emitted by objects near room temperature is infrared. And your television remote will probably work on infrared too.
I have this old Nikon D2h. This 4-megapixel camera is outdated (2003) albeit it is still a very good camera. I can’t set the date anymore and once in the blue moon it misfires. But it shoots at 8 frames per second so it is ideal for sports photography.
Yet I don’t use the camera much anymore. Only when I feel like doing some infrared as the camera is very sensitive to IR. I have no use for a modified camera so this is the second best solution.
Back in the old days of film I shot a few rolls of real IR-film for school projects and I came to love the eerie way the results look like.
So on a sunny day I’ll use the Cokin IR 007 filter (-6 stops) and then process the RAW-files in Lightroom with a preset I made.
Maybe I should do this more often and go out and look for scenes that work very well in infrared.