cat

Concatenate and display file contents.

What it does

cat reads files and prints their contents to standard output. It is commonly used for quick viewing, combining files, and piping data into other commands.

Quick Start

# Display a file
cat file.txt

# Combine files
cat file1.txt file2.txt

Examples

# Number lines
cat -n file.txt

# Show non-printing characters
cat -A file.txt

# Create a file
cat > newfile.txt

# Append to a file
cat >> existing.txt

Notes

Very fast and simple
Not ideal for large files (use less)
Often used in pipelines