Question 1

What is string padding?

Accepted Answer

String padding adds characters to the start or end of a string to reach a target length. Left-padding (padStart in JavaScript, ljust/rjust in Python) is used for right-aligning numbers in columns — '7' becomes '   7' in a 4-wide field. Right-padding (padEnd) is used for left-aligning text — 'name' becomes 'name    ' in an 8-wide column. Zero-padding is a special case of left-padding with '0': '42' becomes '042' with width 3. Common in formatting logs, alignment, fixed-width file formats, and number formatting.

Question 2

What is string truncation with ellipsis?

Accepted Answer

Truncation shortens a string to a maximum length, optionally appending an ellipsis ('...') to indicate the text was cut. For UI display, 'This is a very long product description' becomes 'This is a very lon...' at 20 characters. CSS has the text-overflow: ellipsis property for visual truncation, but for actual string manipulation (API responses, database storage, log messages), programmatic truncation is needed. Word-boundary truncation breaks at a word rather than mid-character, producing 'This is a very...' instead of 'This is a very lon...'.

Question 3

What is string repetition and wrapping?

Accepted Answer

String repetition (repeat) creates a string repeated N times: '-'.repeat(40) creates a 40-character divider line. Useful for generating separator lines, test data, or visual formatting. Text wrapping breaks long text at a specified column width, adding line breaks to prevent lines exceeding the limit — useful for terminal output, email bodies, and fixed-width formats. Word-wrapping breaks only at spaces; hard wrapping breaks exactly at the column regardless of word boundaries.

Question 4

How does center alignment work?

Accepted Answer

Center alignment distributes padding evenly on both sides of a string to center it within a target width. If the padding is odd, the extra character goes to the right side by convention. Example: 'hi'.center(10, '-') in Python gives '----hi----'. In JavaScript: const s='hi'; const total=10; const left=Math.floor((total-s.length)/2); s.padStart(s.length+left).padEnd(total) achieves the same. Center alignment is used in text-based UIs, fixed-width reports, and ASCII art.

String Padding Formatter

Padding

Truncate

Repeat

Word Wrap

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