Shell

Shell may refer to:

Architecture and design

Shell (structure), a thin structure
- Concrete shell, a thin shell of concrete, usually with no interior columns or exterior buttresses
- Thin-shell structure

Seashell, a hard outer layer of a marine animal, found on beaches
Eggshell
Nutshell
Exoskeleton, an external covering of some animals
- Mollusc shell
  - Bivalve shell
  - Gastropod shell
- Shell, of a brachiopod
Turtle shell
Armadillo shell

Electron shell or a principal energy level of electrons outside an atom's nucleus
Nuclear shell model, a principal energy level of nucleons within an atom's nucleus
On shell and off shell, quantum field theory concepts depending on whether classical equations of motion are obeyed

Shell plc formerly Royal Dutch Shell plc, a British multinational oil and gas company
- Shell Oil Company or Shell USA
- Shell Australia
- Shell Canada
- Shell Nigeria
Shell corporation, a type of company that serves as a vehicle for business transactions

Shell (computing), a type of user interface
- Command-line interface, sometimes referred to as command shell
- List of command-line interpreters, programs occasionally referred to as shells
- Web shell, interface that enables a web server to be remotely accessed
Read–eval–print loop, also known as a language shell
Shell account, a user account on a remote server
Secure Shell, cryptographic network protocol
Shellsort or Shell sort, a sorting algorithm by Donald Shell
Shell, an empty expert system

Racing shell, a watercraft
Shell (machinery), each half of a two-piece plain bearing
Coverage shell, the number of defenders guarding the deep portion of the field in American football
Conchiglie, a type of pasta