What is the difference?

I was speaking to a Catholic friend recently who stated that her daughter's first communion was going on at their church and she was having difficulties deciding on which first communion invitations she should choose. Now I am a Baptist and even after she explained it to me I still don't fully understand the difference between our communion as a Baptist and theirs as a Catholic and if there is any at all. We celebrate communion as a choice and don't necessarily send out invitations to a child's first communion. If someone could explain it to me any clearer please feel free, it would be appreciated.