# read in

CEFR C1 · Phrasal verb

Source: https://englishreference.com/word/read-in
Updated: 2026-10-22

## Definition

to bring information from a file or source into a computer program. You use this when a computer needs to process data stored somewhere else.

For teachers: to transfer data from an external source into a computer's memory. The verb is transitive and can be used with or without an object between the verb and particle.

## Examples

- The application must read in the user data first.
- After the system reads in the configuration file, it applies the new security settings automatically.
- Modern data processing pipelines are optimized to read in millions of records per second from distributed cloud storage systems.

## Pitfalls

- Not "The program reads in to the data." but "The program reads in the data." — The particle 'in' should not be followed by 'to' when describing data input.

## Usage notes

- Commonly used in programming, data science, and technical documentation.
- Teaching tip: Contrast this with 'read into', which involves interpreting hidden meanings in a text or situation.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.