Files, Data & Storage terms
64 Files, Data & Storage terms explained in plain English.
- Advanced Data Protection (iCloud)Advanced Data Protection is an optional iCloud security setting that extends end-to-end encryption to most iCloud data, including device backups, photos, notes, and iCloud Drive files.
- Archive FileAn archive file is a single file that contains one or more other files bundled together, often compressed to save space.
- Audio File Types (MP3, WAV, FLAC)Audio files come in different formats that balance quality and file size.
- Churn RateChurn rate (also called attrition rate) is the percentage of customers who stop using a product or service within a defined time period, typically monthly or annually.
- Cloud Storage vs Local StorageLocal storage means keeping files on the device right in front of you, like your computer's hard drive or a USB stick.
- CMR vs SMR hard drivesCMR (conventional magnetic recording) and SMR (shingled magnetic recording) are two methods hard drives use to write data onto spinning platters.
- Cohort AnalysisCohort analysis groups individuals (customers, users, patients) who share a common defining characteristic (typically when they started using a product, when they were first treated, or when they made their first purchase) and tracks their behavior over time.
- Compression (making files smaller)Compression is the process of making a file smaller so it takes up less storage space and is faster to send or download.
- Confidence IntervalA confidence interval is a range of values, constructed from sample data, that is likely to contain the true population value for a parameter (like a mean or proportion).
- Correlation vs CausationCorrelation describes a statistical relationship between two variables -- when one tends to increase or decrease as the other does.
- Corrupt FileA corrupt file is one that has been damaged so that it no longer works properly.
- Customer SegmentationCustomer segmentation is the practice of dividing a company's customers into groups (segments) based on shared characteristics, behaviors, or needs -- and then developing differentiated strategies for each segment.
- Data deduplicationData deduplication is a technique that finds repeated chunks of data and stores them only once, replacing duplicates with small pointers to the single copy.
- Data recoveryData recovery is the process of getting back files that have been deleted, corrupted, or trapped on a failed drive, phone, or memory card.
- Data Scientist vs Data AnalystData analysts and data scientists both work with data but at different levels of complexity and purpose.
- Data StorytellingData storytelling is the practice of communicating analytical insights through a combination of data, visualizations, and narrative context in a way that engages a specific audience and drives understanding or action.
- Database (beginner version)A database is an organized collection of information stored on a computer.
- Descriptive AnalyticsDescriptive analytics is the most fundamental form of data analysis: summarizing and visualizing historical data to understand what has happened in the past.
- Digital legacyA digital legacy is everything you leave behind online: email, social media accounts, photos in the cloud, documents, subscriptions, cryptocurrency, and passwords.
- Digital SignatureA digital signature is an electronic way to prove that a document or message is genuine and has not been tampered with.
- Document vs FileA file is any piece of data saved on a computer with a name and a format, like a photo, a song, or a program.
- Encryption (beginner version)Encryption is a way of scrambling data so that only someone with the right key can read it.
- Encryption at rest vs in transitEncryption at rest scrambles data while it's stored, on a laptop drive, phone, server, or cloud storage, so a stolen device or disk is unreadable without the key.
- Feature EngineeringFeature engineering is the process of creating, selecting, or transforming input variables (features) for machine learning or statistical models to improve their predictive accuracy and business relevance.
- File extensionA file extension is the group of letters after the last dot in a file name, such as .docx for Word documents, .jpg for photos, .pdf for PDFs, and .exe for Windows programs.
- File PathA file path is the address that tells your computer exactly where a file is located.
- File Size (KB, MB, GB explained)File size tells you how much storage space a file takes up.
- ForecastingForecasting is the process of estimating future values of a variable based on historical data, statistical models, and/or expert judgment.
- Funnel AnalysisFunnel analysis tracks how users move through a defined sequence of steps toward a goal (purchase, signup, activation) and measures the percentage who complete each step.
- HeatmapA heatmap is a data visualization that represents numerical values as colors in a two-dimensional grid.
- HistogramA histogram is a data visualization showing the distribution of a numerical variable.
- Hypothesis TestingHypothesis testing is a formal statistical procedure for evaluating whether observed data provides sufficient evidence against a baseline assumption (the null hypothesis).
- Image File Types (JPG, PNG, GIF, WebP)There are several common image file types, each designed for different purposes.
- Lossless vs lossy compressionCompression makes files smaller, and it comes in two kinds.
- Margin of ErrorMargin of error (MOE) is the maximum expected difference between a sample estimate and the true population value, at a specified confidence level (almost always 95%).
- Mean / Median / ModeMean, median, and mode are three measures of central tendency -- each describing what a 'typical' value in a dataset looks like from a different angle.
- MetadataMetadata is information about information.
- OneDrive / Google Drive / iCloudOneDrive, Google Drive, and iCloud are the three most popular cloud storage services.
- Optical character recognition (OCR)Optical character recognition (OCR) is technology that detects text in images, such as scanned documents, photos, screenshots, and PDFs, and converts it into digital text that can be searched, copied, and edited.
- OutlierAn outlier is a data point that falls far outside the typical range of values in a dataset -- either much higher or much lower than the rest of the data.
- OverwriteOverwriting means replacing the contents of an existing file with new data.
- PDFPDF stands for Portable Document Format.
- Permissions (file permissions)File permissions are rules that control who can do what with a file or folder.
- Predictive AnalyticsPredictive analytics uses historical data, machine learning, and statistical models to make forward-looking predictions about individual-level outcomes.
- Prescriptive AnalyticsPrescriptive analytics recommends specific actions to achieve desired outcomes, going beyond descriptive analytics (what happened), diagnostic analytics (why it happened), and predictive analytics (what will happen) to answer 'what should we do?' Prescriptive methods include optimization (finding the mathematically optimal allocation of resources given constraints), simulation (modeling the consequences of different action choices), and decision trees (structuring multi-step decision problems with probabilistic outcomes).
- Probability DistributionA probability distribution is a mathematical function that describes all possible outcomes (values) of a random variable and the probability of each outcome occurring.
- RAID (storage)RAID (redundant array of independent disks) is a way of combining multiple drives into one storage system for better reliability, speed, or both.
- Read-OnlyRead-only means you can open and view a file but you cannot change, edit, or delete its contents.
- Recycle Bin / TrashThe Recycle Bin (on Windows) or Trash (on macOS) is a special folder where deleted files go temporarily before they are permanently removed.
- Regression AnalysisRegression analysis is a collection of statistical methods for modeling the relationship between an outcome variable (dependent variable) and one or more predictor variables (independent variables).
- SamplingSampling is the process of selecting a representative subset (sample) from a larger group (population) to collect data and make inferences about the whole population.
- Scatter PlotA scatter plot (also called a scatterplot or scatter diagram) is a data visualization that places each data point at coordinates defined by two numerical variables -- one on the x-axis and one on the y-axis.
- Shared Drive / Network DriveA shared drive or network drive is a storage location that multiple people can access over a network.
- SMART drive monitoringSMART (Self-Monitoring, Analysis and Reporting Technology) is a feature built into hard drives and SSDs that tracks indicators of drive health, such as reallocated sectors, read errors, temperature, power-on hours, and, for SSDs, remaining wear.
- SpreadsheetA spreadsheet is a digital tool that organizes information into rows and columns, creating a grid of cells.
- Standard DeviationStandard deviation is a measure of variability (spread) in a dataset -- how far individual values typically deviate from the mean (average).
- Statistical SignificanceStatistical significance is a mathematical determination that an observed result is unlikely to have occurred by random chance.
- Storage tiersStorage tiers are levels of storage with different speeds and prices, matched to how often data is used. 'Hot' storage holds frequently accessed data on fast drives and costs more. 'Cool' or 'infrequent access' tiers cost less but charge more to retrieve data. 'Archive' tiers, such as Amazon S3 Glacier Deep Archive or Azure Archive, are extremely cheap for storage but can take hours to retrieve from.
- Sync (file syncing)Syncing means keeping the same files updated and identical across multiple devices or locations.
- Tape backupTape backup stores copies of data on magnetic tape cartridges, most commonly the LTO (Linear Tape-Open) format.
- Text File vs Rich Text FileA plain text file contains only the basic characters you type — letters, numbers, and symbols — with no formatting like bold, italics, or colors.
- Time-Series AnalysisTime-series analysis is a branch of statistical analysis focused on data collected at regular time intervals (daily sales, monthly revenue, hourly website traffic).
- Video File Types (MP4, MOV, AVI)Video files come in different formats, each with its own strengths.
- What is Data?Data is any piece of information that a computer can store, process, or display.