diff for file comparison in Linux CLI - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does the diff command do in Linux?

The diff command compares two files line by line and shows the differences between them.

beginner

How do you use diff to compare two files named file1.txt and file2.txt?

Run diff file1.txt file2.txt. It will show lines that differ between the two files.

beginner

What does the output starting with < and > mean in diff?

Lines starting with < are from the first file, and lines starting with > are from the second file. They show what is different.

intermediate

What option can you add to diff to ignore case differences?

Use diff -i file1.txt file2.txt to ignore case differences when comparing.

beginner

How can diff help in real life?

It helps you quickly see what changed between two versions of a file, like comparing two drafts of a letter or code.

What does the diff command compare?

A Two users

B Two folders

C Two files line by line

D Two processes

diff compares two files line by line to show differences.

Which symbol in diff output shows lines from the second file?

A <

B >

C #

D *

Lines starting with > come from the second file.

How do you ignore case differences when using diff?

A -i

B -v

C -r

D -c

The -i option ignores case differences.

What will diff file1.txt file2.txt show if files are identical?

A Error message

B All lines

C File sizes

D No output

If files are the same, diff shows no output.

Which command shows differences between two files?

A diff

B cat

C ls

D grep

diff is used to compare files and show differences.

Explain how the diff command helps you compare two text files.

Think about how you spot changes between two versions of a note.

Describe a real-life situation where using diff would be useful.

Imagine you wrote a letter twice and want to see what you changed.