🔹 What is a File Format?

A file format defines how data is encoded inside a file.
It determines how a program reads, writes, and interprets the contents of that file.

⚠️ Important: Don’t confuse a file's format with its extension:

• The format refers to how the data is organized and encoded.

• The extension is part of the filename (e.g., .docx, .pdf) that helps the operating system identify which application should open it.

🔧 Changing a File Format

To change the format of a file:

1. Open the file using the appropriate application.

2. Use "Save As" and select the desired format from the “file type” dropdown menu.

3. ❌ Do not just rename the extension, as it won’t convert the file and may make it unusable.

Example:

• Don’t rename document.pdf to document.txt.

• Instead, open the PDF with Adobe Reader and export it to .txt or .docx.

🔄 Interoperability of File Formats

📁 Two Categories of Files:

• Text files – human-readable, encoded as characters (e.g., .txt)

• Binary files – encoded in binary, often only readable by specific programs (e.g., .docx, .jpg)

🔓 Open vs Proprietary Formats

Open formats promote interoperability, meaning the file can be opened and modified with different applications.

📄 Common Document Formats

🖼️ Image Formats

🟦 Raster (Bitmap) Images

• Made up of pixels.

• Lose quality when scaled (pixelation).

• Large file sizes.

🔷 Vector Images

• Made of mathematical shapes.

• Scalable without losing quality.

🎧 Other File Formats