what is antiparticle? Where do they actually exist

an anti particle is a particle common in all aspects (size, weight, etc) to another particle, save the particles charge, an example is an electron and a positron. an electron has a negitive chage, while its antiparticle, the positron, is the same weight/density though has a positive charge.

 

as matter and antimatter cancel each other out when they come into contact and produce pure energy, there is extreemly little naturaly occuring antiparticles.

 

where you can find antiparticles is in some of the larger particle accelerators here on earth where it can be artificialy made.