JavaScript Binary Data — Quiz

Question 1 of 16

What does an ArrayBuffer provide?

Answer options A A fixed or resizable raw binary data buffer B A locale-aware formatter C A Promise queue D A string parser

ArrayBuffer provides raw binary storage; views such as TypedArrays and DataView interpret its bytes.

Question 2 of 16

What does a TypedArray buffer property provide?

Answer options A Its underlying binary buffer B A locale formatter C A Promise D A string copy

The buffer property exposes the underlying ArrayBuffer or SharedArrayBuffer storage used by the view.

Question 3 of 16

What does Uint8Array represent?

Answer options A A view whose elements are 8-bit unsigned integers B A view of UTF-16 code units only C A date-time object D A shared-memory lock

Uint8Array is a TypedArray view with 8-bit unsigned integer elements.

Question 4 of 16

Why can two TypedArrays observe the same bytes?

Answer options A They can be views over the same underlying buffer B TypedArrays copy every value into every other view C The JavaScript engine converts all arrays automatically D They must use the same constructor

Multiple views can reference the same ArrayBuffer storage with different element types and offsets.

Question 5 of 16

What does byteOffset describe?

Answer options A Where the view starts in the underlying buffer B The number of elements in the view C The maximum integer value D The byte order used by DataView

byteOffset is the starting byte position of the view within its buffer.

Question 6 of 16

What happens when values do not fit Uint8Array?

Answer options A They are converted using the Uint8 conversion semantics B They always throw RangeError C They become strings D They are ignored

TypedArray element assignment uses the conversion rules for that element type, including modulo-style integer conversion for Uint8Array.

Question 7 of 16

What distinguishes Uint8ClampedArray?

Answer options A Values are converted with unsigned 8-bit clamping semantics B It stores arbitrary-size integers C It always uses BigInt D It shares memory across workers automatically

Uint8ClampedArray uses the Uint8Clamp conversion rather than ordinary Uint8 conversion.

Question 8 of 16

Which values belong in BigInt64Array?

Answer options A BigInt values B Number values only C Strings representing integers D Dates

BigInt64Array elements have BigInt content and therefore use BigInt values.

Question 9 of 16

Why use DataView for binary formats?

Answer options A It lets code choose the numeric type and endianness per access B It only stores strings C It automatically chooses a locale D It prevents all mutation

DataView provides explicit byte-oriented reads and writes with selectable numeric types and endianness.

Question 10 of 16

What does the littleEndian argument control?

Answer options A The byte order used to encode or decode multi-byte values B The array length C Whether the buffer is shared D The numeric range

For multi-byte DataView operations, littleEndian selects little-endian byte order when true; false uses big-endian order.

Question 11 of 16

Why are BigInt DataView methods useful?

Answer options A They preserve integer values outside Number’s safe-integer range B They convert values to floating point C They create strings automatically D They make memory shared

BigInt64 and BigUint64 methods allow exact 64-bit integer access using BigInt values.

Question 12 of 16

How do TypedArrays relate to ordinary array methods?

Answer options A They provide many familiar indexed collection methods while enforcing element types B They are plain objects with no iteration C They can only be accessed through DataView D They cannot be mapped

TypedArrays support many collection operations while retaining typed, fixed-width element storage.

Question 13 of 16

What does copyWithin do?

Answer options A It copies elements within the same TypedArray without changing its length B It allocates a new ArrayBuffer every time C It converts bytes to strings D It changes the element type

copyWithin moves values inside the same typed array and keeps its length unchanged.

Question 14 of 16

What does a resizable ArrayBuffer add?

Answer options A The ability to resize within a declared maximum byte length B Automatic type conversion C Shared memory synchronization D Automatic serialization

A resizable ArrayBuffer can change its byte length through resize(), subject to its maximum byte length.

Question 15 of 16

What happens to the original after ArrayBuffer transfer?

Answer options A Its data is moved and the original becomes detached B Both buffers keep independent copies C The original becomes a SharedArrayBuffer D The original converts to a DataView

Transfer moves the buffer’s backing data and detaches the original ArrayBuffer.

Question 16 of 16

What does ArrayBuffer.isView detect?

Answer options A Whether a value is a view such as a TypedArray or DataView B Whether a value is any object C Whether a buffer is resizable D Whether an array is sparse

ArrayBuffer.isView reports whether a value is an ArrayBuffer view, including TypedArrays and DataView.

JavaScript Binary Data — Quiz