If you ever need to file an insurance claim for damages to your home or a police report for stolen items, you will need to produce a list of affected property. You could always write out a list and type it up, but that would take hours. Here is an easy-peasy way to take a home inventory.
Walk around your home with your cellphone and make a video of everything. I do mean everything. Open closets, drawers, and cabinets. Take closeups or still pictures of the serial numbers of electronic devices and anything else where detail is important to prove the value or uniqueness of the item. Then copy that video and photos to a flash drive and store it in a safe place, preferably a safe deposit box or somewhere else outside your home.
If you ever want a more detailed list, you now have this video to help you compile a list of what you own. The list can be done as a spreadsheet or a simple document. Documenting the items room by room will assure that all is captured and recorded in the event, heaven forbid, that you ever need it.