Basic data types - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a data type in C?

A data type in C tells the computer what kind of data a variable can hold, like numbers or characters.

beginner

Name the four basic data types in C.

The four basic data types in C are int (for whole numbers), float (for decimal numbers), char (for single characters), and double (for double precision decimal numbers).

beginner

What is the difference between int and float?

int stores whole numbers without decimals, while float stores numbers with decimals (fractional parts).

intermediate

How much memory does a char usually take in C?

A char usually takes 1 byte of memory, enough to store one character.

intermediate

Why do we use double instead of float sometimes?

double stores decimal numbers with more precision and uses more memory than float. Use it when you need more accurate decimal values.

Which C data type is used to store whole numbers?

A int

B float

C char

D double

int is used for whole numbers without decimals.

What data type would you use to store a single letter?

A int

B char

C float

D double

char stores a single character or letter.

Which data type uses more memory and stores more precise decimal numbers?

A double

B float

C char

D int

double uses more memory and stores decimal numbers with higher precision than float.

How many bytes does a char usually take?

A 4 bytes

B 8 bytes

C 2 bytes

D 1 byte

A char usually takes 1 byte of memory.

Which data type would you choose to store the number 3.14?

A int

B char

C float

D int and char

float is used to store decimal numbers like 3.14.

Explain the main differences between int, float, char, and double in C.

Think about what kind of data each type holds and their precision.

Why is it important to choose the correct data type when declaring a variable in C?

Consider how data type affects memory and accuracy.