Spike's diary

It's a journal.

Spike Witwicky keeps a diary, in which he records his early interactions with the Autobots.

Fiction

The Transformers cartoon

Perhaps to cope with the more boring moments of life on an oil rig, Spike Witwicky kept a diary. Following the attack on the oil rig and his rescue by the Autobots, Spike entrusted his thoughts once more to the diary's pages. Subjects covered were the possibility that the Transformers were from another time, the certainty they were living and thinking beings, and the incredulity the past 24 hours were real. More than Meets the Eye, Part 2

When the attempt to stop the Decepticons' theft of ruby crystals in Burma failed and the Autobots had to return to base to take care of their injured, Spike Witwicky noted in his diary how Optimus Prime genuinely cared about the well-being of his troops and that he'd make a neat president.

Some time after the Decepticons' starship had crashed into the ocean, Spike wrote in his diary about the various governments of the world supplying the Autobots with what they needed to fix their ship and get back home. Spike was enthusiastic about governments agreeing with one another on something, the prospect of him and his dad going to Cybertron and the Decepticons' defeat. More than Meets the Eye, Part 3

Ladybird Books continuity

The morning after a thunderstorm, Spike wrote in his diary about the Autobots' unfamiliarity with thunder and lightning, and commented on how odd a world Cybertron must be. Autobots' Lightning Strike After a peaceful week of zero Decepticon activity, Spike wondered in his diary what they could be up to. Megatron's Fight for Power

Notes

• The idea of Spike's diary being used as a framing device was limited to "More than Meets the Eye'", and didn't appear in any further episodes. However, it was one of several concepts culled from the mini-series for use in the early Ladybird Books.
• A human journal wouldn't be used as a storytelling element again until 2011, with Raf's Notes contributing to the episodes of the Prime cartoon.