each frame had a single-character type code associated with it. most frames would be "i" (for "information" types) but other types included response frames, mailbox pages, or gateway pages. special frame types could also be specified which caused the follow-on frame to be automatically displayed, with or without the usual clear-screen code, as soon as the current frame had finished being transmitted. these were mainly used by "dynamic frames", as it provided a mechanism to continue animations which would not otherwise fit within the number of characters available in a standard frame.