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(operating system)
A string of words and characters that you type in to authenticate yourself. Passphrases differ from passwords only in length. Passwords are usually short - six to ten characters. Passphrases are usually much longer - up to 100 characters or more. Their greater length makes passphrases more secure. Modern passphrases were invented by Sigmund N. Porter in 1982.

Phil Zimmermann's popular encryption program PGP, for example, requires you to make up a passphrase that you then must enter whenever you sign or decrypt messages.
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A secret word or code used to serve as a security measure against unauthorized access to data. It may be used to log onto a computer, mobile device, network or website or to activate newly installed software in the computer. However, without additional measures such as biometric identification, the computer can only verify the legitimacy of the password, not the legitimacy of the user (see biometrics).

Password Synonyms
"Passphrase," "passcode" and "PIN" are synonymous terms for this type of identity mechanism. A "key" is sometimes used as a synonym for password; however, this usually refers to a code generated to encrypt and decrypt messages or to unlock software. See PIN, password manager, public key cryptography and NCSC.

Password Tips from the NCSC

CHANGE PASSWORD FREQUENTLY - The longer you use a password, the higher the risk.

USE GOOD PASSWORDS - Don't use persons, places or things that can be identified with you.

DON'T DISCLOSE YOUR PASSWORD - Your password is as valuable as the information it protects.

INSPECT YOUR DATA - If you suspect someone has tampered with your files, report it immediately.

NEVER LEAVE AN ACTIVE TERMINAL UNATTENDED - Always log out or lock your terminal before leaving it.

REPORT SUSPECTED COMPUTER ABUSE - Whether directed against you or not, abuse or misuse of your computer resources only hinders the timely completion of your tasks.

Check Your Password Strength
Go to and type in your password to find out just how secure it is.
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* Do consider using a common passphrase and then altering it with each site in a standard way.
"Our paper shows that passphrase requirements such as a 15-character minimum length deter the vast majority of IU users (99.98 percent) from reusing passwords or passphrases on other sites," they write.
Use passphrases, rather than passwords, to control access to computer networks.
Using a string of random words to create a "passphrase" such as "swan windmill heartbeat soccer" rather than a shorter alphanumeric combination not only helps to create a more secure password, but also one that a user is actually more likely to remember.
"For example, you log in with a passphrase and then you generate a one-time code from a secured device such as a smart card, token or an application on your smartphone.
Also, we advise the use of long and complex passwords, or a passphrase for these purposes; you can use a password manager to create and store passwords in a safe place.
"Instead of using a simple word or number sequence, you should create a passphrase by joining three or four unrelated words to form a long single word.
To make it difficult for villains to guess, create a passphrase you'd remember - "GandalftaughtPotter2usetheForce" for example.
From the registered mobile number, the voice biometrics technology compares the customer's spoken passphrase to a registered voiceprint.
The user then click the file icon and pops out a box showing the Enter password and Repeat password text fields, Passphrase quality.
The ability to convert characters to words and words to images is the basis of forming a strong passphrase unique to you.
Or use a passphrase that is easy to remember, but change some of the letters to numbers, such as "E" to "3." For instance, "ILoveCaliforniaSocietyofCPAs" is changed to "!LOVc@LifOrniaSOcietyofCP@s."