How do companies usually contact you about interviews?

After you’ve applied for a job, how do companies get in contact with you?

Do they call you for an interview?
Do they shoot you an email telling you to contact them?
If they send you an email, do they ever put attachments on?

The reason I’m asking is my ‘professional’ email has a tiny limit on file size. It forwards emails to my bigger account, but I am worried that if they tried sending me an email with an attachment(information and whatnot) it might get rejected and sent back.

So have you ever heard of any companies contacting applicants in such a way?