Some signals carry encryption and specify use conditions ( such as " may not be recorded " or " may not be viewed on displays larger than 1 m in diagonal measure ") backed up with the force of law under the WIPO Copyright Treaty and national legislation implementing it, such as the U. S. Digital Millennium Copyright Act.

Some consider emoticons and ASCII art, like smiley faces, to be leet, while others maintain that leet consists of only symbolic word encryption.

Some encryption schemes can be proven secure on the basis of the presumed difficulty of a mathematical problem, such as factoring the product of two large primes or computing discrete logarithms.

Some special and specific algorithms have been developed to aid in attacking some public key encryption algorithms-both RSA and ElGamal encryption have known attacks that are much faster than the brute-force approach.

Some modern scramblers are actually encryption devices, the name remaining due to the similarities in use, as opposed to internal operation.

Some are no longer relevant given the ability of computers to perform complex encryption, but his second axiom, now known as Kerckhoffs's principle, is still critically important.

( Some encryption algorithms, known as nonmalleable ones, prevent this, but others do not.

Some secure cryptoprocessors contain dual processor cores and generate inaccessible encryption keys when needed so that even if the circuitry is reverse engineered, it will not reveal any keys that are necessary to securely decrypt software booted from encrypted flash memory or communicated between cores.

Some phones include a special monitor mode ( activated with secret codes or special software ) which displays GSM operating parameters such as encryption while a call is being made.

Some virtual networks may not use encryption to protect the data contents.

Some modern modes of operation combine encryption and authentication in an efficient way, and are known as authenticated encryption modes.

Some of the methods of protecting e-business security and keeping information secure include physical security measures as well as data storage, data transmission, anti-virus software, firewalls, and encryption to list a few .< ref name =" canada "> Industry Canada | Industrie Canada.

Some protocols like FTP and Telnet transfer data and passwords in clear text, without encryption, and network scanners can see this data.

Some web servers will not communicate with a client unless it has a 128-bit encryption capability installed on it.

Some basic information about the MIFARE Classic or MIFARE DESFire chip can be read by any ISO / IEC 14443 type A compatible reader, but Oyster-specific information cannot be read without access to the encryption used for the Oyster system.

; Secret system: Some encryption systems will claim to rely on a secret algorithm, technique, or device ; this is categorized as security through obscurity.

Some of the newer pastebins provide features for comparing two or more pastes, synchronous notifications through IRC or XMPP, paste histories, encryption, password protection, and virtual subdomains.

* Some servers require passwords to be stored using reversible encryption.

Some also provide plausible deniability with deniable encryption techniques.

Some examples of file encryption software are GNU Privacy Guard and PGP ).

Some disk encryption systems offer two levels of Plausible Deniability, which might be useful in case a user is required to reveal the password of an encrypted volume.

Some disk encryption software allows encrypted volumes to be resized.

Some weapons systems have become obsolescent while still in production, and some while still under development.

Some phonetic features, for example glottal catch or murmur, are sometimes to be assigned to segmental phonemics and sometimes to accentual systems.

Some school systems provide written instructions to principals and teachers designating when certain information is to be recorded on cumulative record forms and explaining how the information is to be summarized and used.

Some US School districts and systems return to school in August.

Some belief systems, such as those in the Abrahamic tradition, hold that the dead go to a specific plane of existence after death, as determined by a god, gods, or other divine judgment, based on their actions or beliefs during life.

Some, like Hernando De Soto, argue that much of the poverty in the Third World countries is caused by the lack of Western systems of laws and well-defined and universally recognized property rights.

Some home sewage treatment systems use biological treatment, usually beds of plants and aquaria, that absorb nutrients and bacteria and convert greywater and sewage to clear water.

Some systems are vacuum-insulated, acting something like large thermos bottles.

Some proven intensive, low-effort food-production systems include urban gardening ( indoors and outdoors ).

Some systems used a CD-ROM drive to make the files available.

Some bicycle parts, particularly hub-based gearing systems, are complex, and many cyclists prefer to leave maintenance and repairs to professional bicycle mechanics.

Some systems have proposed as many as 90 subspecies, while recent DNA analysis has identified as few as five clades.

Some modern editing systems can use OCR techniques to read BITC in situations where other forms of timecode are not available.

Some linguists, such as John DeFrancis and J. Marshall Unger have argued that genuine ideographic writing systems with the same capacities as natural languages do not exist.

Some writing systems of the world, notably the Arabic and Hebrew scripts, and derived systems such as the Urdu, Persian, Yiddish, Jawi, and Ladino scripts, are written in a form known as right-to-left ( RTL ), in which writing begins at the right-hand side of a page and concludes at the left-hand side.

Some systems used both codes and ciphers in one system, using superencipherment to increase the security.

Some take the approach of looking for coherent justifications of established copyright systems, while others start with general ethical theories, such as utilitarianism and try to analyse policy through that lens.

Some critics of this approach feel that while these models approach biological reality as a representation of how the system works, they lack explanatory powers because complicated systems of connections with even simple rules are extremely complex and often less interpretable than the system they model.

Some jurisdictions give priority to motorized traffic, for example setting up one-way street systems, free-right turns, high capacity roundabouts, and slip roads.

Some masters use different systems, or even no system at all.

Some light rail systems may run on a narrower gauge.

Some missiles can be fitted with any of a variety of navigation systems ( Inertial navigation, TERCOM, or satellite navigation ).

Some GC systems allow such other resources to be associated with a region of memory that, when collected, causes the other resource to be reclaimed ; this is called finalization.

Some, like VirtualBox and VMware Player run on Windows and Linux hosts and can run many other operating systems.