Pockets
These pictures show some of the many possibilities for internal pockets (for pens, phones, business cards…) which are usually sewn to one of the internal divisions and can be made to fit nearly anything. However, it is often simpler to manage things such as cables, memory sticks and so on with a matching pouch to keep it all together.
Full width internal “slip” pockets usually hold flat things such as laptops or documents and effectively form additional compartments within a case or bag.
Zips can be fitted into the main panels which will usually then have a lining within the case or bag to contain the pocket itself. The last pictures show “newspaper” slips (some with zips for airport/wheeled trolley handles).