Toe jam is that yucky stuff that can accumulate between your toes and develop a foul-smelling odour. Toe jam consists of an accumulation of a number of different things in the tight spaces between the toes. This includes sock lint (especially from new socks), dead skin cells, sweat and other debris. Infections can develop in that unhygienic environment.
The best way to get rid of toe jam is to practice good foot hygiene. This means washing your feet, especially between the toes thoroughly and then drying carefully between the toes and doing this every day. Wearing open-toe shoes or going barefoot as often as possible to let the air circulate is also helpful. Changing the socks during the day, especially after exercise can also be helpful.
If you suspect that an infection, either bacterial or fungal (tinea) has developed and see a podiatrist for more advice and help.