spellcheck

Spellcheck is a software feature that identifies misspelled words in text and suggests corrections. It is commonly integrated into word processors, browsers, email clients, code editors, and mobile keyboards. Most spellcheckers rely on a lexicon or dictionary of correctly spelled words and a set of rules to flag unfamiliar forms and typographical errors. They may also consider inflected or capitalized forms, proper nouns, and accepted loanwords.

Two main approaches are used in spellchecking: dictionary-based and context-based. Dictionary-based spellcheckers compare words to a reference list; if a word is not found, they generate correction candidates using edit distance algorithms (such as Levenshtein distance) or phonetic similarity. Contextual approaches use language models to rank candidates by plausibility within surrounding text, reducing false positives from proper nouns or technical terms.

Autocorrect and suggestions are common features. Some systems automatically replace a misspelled word with the top candidate or present a short list of alternatives. Tools may also offer additional features such as hyphenation fixes, punctuation spacing adjustments, and integration with grammar checks.

Limitations and challenges include misidentifying correctly spelled words, reliance on dictionary coverage, and difficulties with proper nouns, code snippets, and multilingual or highly technical content. Ongoing developments in spellchecking increasingly incorporate contextual cues and machine learning to improve accuracy and adaptability across languages.