TXT
TXT most commonly refers to [[Tomorrow X Together]], a South Korean boy band formed by Big Hit Music (now under HYBE) in 2019.[1] For other uses, see TXT (disambiguation). The group consists of five members: Yeonjun, Soobin (leader), Beomgyu, Taehyun, and HueningKai.[2] Known for their youthful energy, intricate storytelling in music, and genre-blending style that incorporates pop, rock, and electronic elements, TXT debuted on March 4, 2019, with the extended play (EP) The Dream Chapter: Star, featuring the lead single "Crown."[3] Their name, read as "tomorrow by together," symbolizes five individuals coming together to form a brighter future.[1]Technology and Computing
Text File Format
The .txt file format represents a plain text file extension used to store unformatted text data without any embedded formatting, styling, or proprietary codes, making it one of the simplest and most basic file types in computing.[4] These files consist solely of sequences of characters, typically delimited by line breaks, and are designed for human readability and basic data interchange across systems.[5] The origins of the .txt format trace back to the early days of computing in the 1960s and 1970s, when plain text files emerged as a fundamental way to handle data on systems like those from IBM and early UNIX environments, with the three-letter .txt extension becoming standardized through file naming conventions adopted in operating systems such as MS-DOS in the 1980s.[6] This convention built on earlier practices from CP/M (1974), where file extensions helped identify content types, and MS-DOS popularized .txt for generic text files via tools like Notepad, ensuring broad adoption in personal computing.[7] Common uses of .txt files include software development for source code snippets, configuration files (e.g., .ini or custom .txt configs), and data exchange between applications, such as log files or simple databases exported as delimited text. A representative example is the README.txt file, often included in software distributions to provide installation instructions and usage notes in a universally accessible format.[8] Key advantages of the .txt format lie in its universal compatibility across operating systems like Windows, macOS, and Linux, as well as text editors such as Microsoft Notepad, Vim, and TextEdit, without requiring specialized software.[6] This portability stems from its minimal structure and small file size, which avoids bloat from metadata or binary elements, facilitating easy transfer and editing even on resource-constrained systems.[8] .txt files encode characters primarily using standards like ASCII or UTF-8 to represent text data. ASCII, the American Standard Code for Information Interchange, uses 7-bit encoding to support 128 basic characters (including English letters, digits, and symbols), serving as the foundational scheme for early .txt files and ensuring compatibility with legacy systems.[9] For modern multilingual support, UTF-8 has become the preferred encoding, as a variable-length Unicode transformation format that backward-compatibly extends ASCII while handling over a million characters from global scripts, recommended for interchange in plain text files.[10]DNS Resource Record
The TXT resource record is a type of Domain Name System (DNS) resource record designed to associate arbitrary text strings with domain names, allowing for the storage of descriptive or machine-readable data without predefined semantics.[11] Introduced in the original DNS specifications, TXT records provide flexibility for domain administrators to attach human-readable notes or structured information, such as authentication policies or verification tokens, directly to a domain or subdomain.[11] The content of a TXT record is domain-specific, meaning its interpretation depends on the context in which it is queried, enabling diverse uses across network protocols and services.[11] Historically, TXT records were defined in RFC 1035, published in November 1987, as part of the core DNS protocol standards to hold "descriptive text" for informational purposes.[11] Subsequent developments expanded their utility; for instance, RFC 1464 in May 1993 proposed using TXT records to store arbitrary string attributes in a structured format, supporting multi-line text and key-value pairs to facilitate broader applications beyond simple notes.[12] These evolutions have made TXT records a foundational element in modern DNS for both legacy and emerging protocols. In terms of technical structure, a TXT record follows the standard DNS resource record format: it consists of an owner name (the domain or subdomain), a time to live (TTL) value indicating caching duration, the Internet class (IN), the type identifier (TXT, numeric value 16), and resource data (RDATA) comprising one or more variable-length character strings.[11] Each character string in the RDATA is prefixed by a one-octet length field and limited to 255 octets, allowing concatenation of multiple strings to form longer entries while adhering to DNS message size constraints.[11] This binary wire format ensures efficient transmission, with textual representations in zone files using quotes to delimit strings, such as "string1" "string2" for multi-part data.[11] Key applications of TXT records include email security mechanisms like Sender Policy Framework (SPF), which uses TXT records to specify authorized mail servers for a domain and prevent spoofing, as defined in RFC 7208.[13] DomainKeys Identified Mail (DKIM) similarly relies on TXT records under the _domainkey subdomain to publish public keys for verifying email signatures, per RFC 6376.[14] Additionally, TXT records facilitate domain ownership verification for services like Google Workspace, where a unique token is added as a TXT entry to confirm control during setup.[15] They also support custom metadata, such as DMARC policies or application-specific identifiers, providing a versatile mechanism for protocol extensions without requiring new record types. For example, an SPF TXT record might appear in zone file syntax asexample.com. 3600 IN TXT "v=spf1 include:_spf.google.com ~all", authorizing Google's mail servers while soft-failing others.[13] A DKIM record could be structured as selector._domainkey.example.com. 3600 IN TXT "v=DKIM1; k=[rsa](/page/RSA); p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQD...", encoding the public key for signature validation.[14] These examples illustrate how TXT records balance simplicity with extensibility in practical DNS deployments.