• ideas
• trade names, symbols or logos
• detailed knowledge

Registration of intellectual property provides a public record of the idea. This can be done in the US by

• patents (via US Patent & Trademark Office)
• copyrights (via Library of Congress)
• trademarks
• trade secrets

Company policies generally define boundaries between personal and company-related creativity. Though the policies are supposed to protect both you and the company, they generally protect the company much, much better. You may be forced to give your ideas over to the company, even if you come up with them substantially on your own time and with your own resources, if the company gives you even modest support (e.g. copier, telephone, Web searches, clerical assistance).

There are two critical steps in obtaining a public record of your ideas: "reduction to practice" and application. Reduction to practice means to take the idea and make it tangible. This enables protection from (for instance) someone else making money from your idea. Record in a notebook, with dates and places

• photos, sketches, drawings, and diagrams
• tests (including descriptions and results)
• modifications
• problems (and solutions as available)
• bills of materials
• financial contributors
• project plans, dates, and critical paths
• agreements and records
• receipts and cancelled checks
• correspondence (e.g. with vendors, consultants, and investors)

This detailed information separates your idea from similar concepts of other inventors. A patent application includes

• title
• background
• summary
• description of invention (brief, then detailed)
• claims (features that distinguish invention from "prior art")
• abstract
• drawings (there are specs on paper, ink, form size, margins, line weight, hatching/shading, scale, characters, symbols, legends, views, and transmission)
• declaration
• transmittal letter
• payment
• return receipt postcard

...all of which goes to the USPTO.

Publishing Related Inventions

Sometimes companies will place incremental improvements to an existing invention in the public domain. Pending patents are tied up (and confidential) for at least 18 months, and innovation goes on. Any incremental changes to the design you've patented (or applied for a patent for) are not covered by the initial patent. A company may instead opt to place the improvements in the public domain, to keep anyone else from getting the patent on the improved invention.