A register may refer to any of the following:
1. With a CPU (central processing unit) and memory, the terms internal register or register refer to the latches that store a single character. The register capacity or register size is the amount of bits in a register is known as the register's width. Instructions flow at a rate as large as the register size, which is either 16, 32, or 64-bits wide.
Registers can only handle data that are smaller than their bit size. For example, if a program is designed to process 64-bit instructions, a processor with a 32-bit register would not be able to run that program.
2. Register describes sending information to a company about yourself or the product you have purchased. In many cases, registering allows you access to technical support from a company or receive a free product or service.
Most companies do not require online registration, but product activation for operating systems is always required.
3. With online services, registration is creating an account with an online service. For example, before using the Computer Hope forums, you must register. Once registered with an online service, log into your account using a username and password you created during the registration and access your settings, messages, and information.
What is a registration agreement?
Before starting the registration, most online services will present you with a registration agreement. This agreement lists rules you must follow to keep your account and use the online service. Disobeying any of the rules in the agreement could result in your account being banned or deleted.
Online services without a registration agreement have a TOS (terms of service).
4. With sound, a register refers to how high a note sounds. Essentially, a higher register means a higher pitch.
5. When spelled as "registar," it may be a misspelling for register (mentioned above) or a domain name registrar.