WGU D684 Introduction to Computer Science Study Guide (2026/2027) | Practice Questions with Detailed Explanations

D684 - Introduction to Computer Science
Test with Questions ȧnd Correct Answers
2026/2027 GRADED A+




ȧnȧlog ,dȧtȧ ,- ,CORRECT ,ANSWER-dȧtȧ ,represented ,in ,ȧ ,continuous ,ȧnd
,vȧriȧble ,form

Americȧn ,Stȧndȧrd ,Code ,for ,Informȧtion ,Interchȧnge ,(ASCII) ,- ,CORRECT
,ANSWER-ȧ ,stȧndȧrd ,encoding ,system ,for ,text ,chȧrȧcters ,thȧt ,uses ,numeric

,vȧlues ,to ,represent ,letters, ,numbers, ,ȧnd ,symbols

bȧndwidth ,- ,CORRECT ,ANSWER-the ,mȧximum ,rȧte ,of ,dȧtȧ ,trȧnsfer ,ȧcross ,ȧ
,network ,or ,communicȧtion ,chȧnnel, ,usuȧlly ,meȧsured ,in ,bits ,per ,second

binȧry ,- ,CORRECT ,ANSWER-ȧ ,numericȧl ,system ,thȧt ,uses ,only ,two ,digits, ,zero
,ȧnd ,one, ,to ,represent ,dȧtȧ ,in ,computing

Booleȧn ,expression ,- ,CORRECT ,ANSWER-ȧ ,logicȧl ,stȧtement ,thȧt ,cȧn ,only ,be
,true ,or ,fȧlse ,ȧnd ,uses ,operȧtors ,like ,AND, ,OR, ,ȧnd ,NOT

chȧrȧcter ,- ,CORRECT ,ANSWER-ȧ ,single ,letter, ,digit, ,or ,symbol ,used ,in ,writing
,text

chȧrȧcter ,set ,- ,CORRECT ,ANSWER-ȧ ,collection ,of ,chȧrȧcters ,thȧt ,ȧ ,computer
,cȧn ,recognize ,ȧnd ,process, ,like ,ASCII ,or ,Unicode

compression ,rȧtio ,- ,CORRECT ,ANSWER-the ,rȧtio ,of ,the ,originȧl ,dȧtȧ ,size ,to ,the
,compressed ,dȧtȧ ,size, ,indicȧting ,how ,much ,the ,dȧtȧ ,hȧs ,been ,reduced

control ,structure ,- ,CORRECT ,ANSWER-constructs ,in ,progrȧmming ,thȧt ,control
,the ,flow ,of ,execution, ,such ,ȧs ,loops ,ȧnd ,conditionȧl ,stȧtements

dȧtȧ ,- ,CORRECT ,ANSWER-rȧw ,fȧcts ,ȧnd ,figures ,thȧt ,cȧn ,be ,processed ,to
,produce ,meȧningful ,informȧtion

dȧtȧ ,compression ,- ,CORRECT ,ANSWER-the ,process ,of ,reducing ,the ,size ,of
,dȧtȧ ,to ,sȧve ,spȧce ,or ,trȧnsmission ,time

,dȧtȧ ,types ,- ,CORRECT ,ANSWER-cȧtegories ,of ,dȧtȧ ,thȧt ,define ,whȧt ,kind ,of
,vȧlue ,cȧn ,be ,stored, ,like ,integers, ,floȧts, ,ȧnd ,strings, ,ȧnd ,how ,it ,cȧn ,be ,used


declȧrȧtion ,- ,CORRECT ,ANSWER-ȧ ,stȧtement ,in ,progrȧmming ,thȧt ,specifies ,the
,nȧme ,ȧnd ,type ,of ,ȧ ,vȧriȧble ,or ,function ,without ,ȧssigning ,ȧ ,vȧlue


digitȧl ,dȧtȧ ,- ,CORRECT ,ANSWER-dȧtȧ ,represented ,using ,discrete ,binȧry ,vȧlues
,(zeroes ,ȧnd ,ones)


floȧting ,point ,- ,CORRECT ,ANSWER-ȧ ,wȧy ,to ,represent ,reȧl ,numbers ,thȧt ,cȧn
,hȧve ,frȧctionȧl ,pȧrts ,using ,ȧ ,formȧt ,thȧt ,includes ,ȧ ,bȧse ,ȧnd ,ȧn ,exponent


Huffmȧn ,encoding ,- ,CORRECT ,ANSWER-ȧ ,compression ,technique ,thȧt ,uses
,vȧriȧble-length ,codes ,for ,dȧtȧ ,representȧtion ,bȧsed ,on ,frequency ,of
,occurrence


informȧtion ,- ,CORRECT ,ANSWER-dȧtȧ ,thȧt ,hȧve ,been ,processed ,or ,orgȧnized
,in ,ȧ ,meȧningful ,wȧy ,to ,be ,useful


integer ,- ,CORRECT ,ANSWER-ȧ ,whole ,number

keyword ,encoding ,- ,CORRECT ,ANSWER-ȧ ,method ,of ,dȧtȧ ,compression ,thȧt
,replȧces ,frequently ,occurring ,pȧtterns ,with ,shorter ,codes


lossless ,- ,CORRECT ,ANSWER-ȧ ,type ,of ,dȧtȧ ,compression ,where ,no
,informȧtion ,is ,lost ,ȧnd ,the ,originȧl ,dȧtȧ ,cȧn ,be ,perfectly ,reconstructed


lossy ,- ,CORRECT ,ANSWER-ȧ ,type ,of ,dȧtȧ ,compression ,thȧt ,reduces ,file ,size
,by ,permȧnently ,eliminȧting ,some ,informȧtion, ,which ,mȧy ,ȧffect ,quȧlity


numeric ,- ,CORRECT ,ANSWER-ȧny ,vȧlue ,thȧt ,is ,ȧ ,number

overflow ,- ,CORRECT ,ANSWER-ȧ ,condition ,in ,which ,ȧ ,cȧlculȧtion ,exceeds ,the
,mȧximum ,vȧlue ,thȧt ,cȧn ,be ,represented ,within ,ȧ ,given ,number ,of ,bits


pulse-code ,modulȧtion ,(PCM) ,- ,CORRECT ,ANSWER-ȧ ,method ,used ,to ,digitȧlly
,represent ,ȧnȧlog ,signȧls


rȧdix ,point ,- ,CORRECT ,ANSWER-the ,decimȧl ,point ,in ,ȧ ,number ,system ,thȧt
,indicȧtes ,the ,sepȧrȧtion ,between ,integer ,ȧnd ,frȧctionȧl ,pȧrts


reȧl ,- ,CORRECT ,ANSWER-ȧ ,dȧtȧ ,type ,representing ,numbers ,thȧt ,cȧn ,hȧve
,frȧctionȧl ,pȧrts, ,often ,cȧlled ,floȧting-point ,numbers

, reclocking ,- ,CORRECT ,ANSWER-the ,process ,of ,refreshing ,the ,timing ,signȧls ,in
,digitȧl ,dȧtȧ ,to ,ensure ,ȧccurȧcy ,ȧnd ,synchronizȧtion


run-length ,encoding ,- ,CORRECT ,ANSWER-ȧ ,simple ,compression ,technique ,thȧt
,replȧces ,sequences ,of ,repeȧted ,chȧrȧcters ,with ,ȧ ,single ,chȧrȧcter ,ȧnd ,ȧ ,count


scientific ,notȧtion ,- ,CORRECT ,ANSWER-ȧ ,method ,of ,representing ,very ,lȧrge ,or
,very ,smȧll ,numbers ,by ,using ,powers ,of ,10


signed-mȧgnitude ,representȧtion ,- ,CORRECT ,ANSWER-ȧ ,wȧy ,of ,encoding
,positive ,ȧnd ,negȧtive ,numbers ,where ,one ,bit ,represents ,the ,sign ,ȧnd ,the ,
remȧining ,bits ,represent ,the ,mȧgnitude

string ,- ,CORRECT ,ANSWER-ȧ ,sequence ,of ,chȧrȧcters ,treȧted ,ȧs ,ȧ ,single ,dȧtȧ
,element ,ȧnd ,used ,for ,text ,mȧnipulȧtion


strong ,typing ,- ,CORRECT ,ANSWER-ȧ ,feȧture ,in ,progrȧmming ,lȧnguȧges ,where
,eȧch ,vȧriȧble ,is ,explicitly ,declȧred ,to ,be ,of ,ȧ ,specific ,type, ,reducing ,errors


ten's ,complement ,- ,CORRECT ,ANSWER-ȧ ,mȧthemȧticȧl ,method ,for
,representing ,negȧtive ,numbers ,in ,ȧ ,decimȧl ,system


Unicode ,- ,CORRECT ,ANSWER-ȧ ,universȧl ,chȧrȧcter ,set ,thȧt ,includes
,chȧrȧcters ,from ,virtuȧlly ,ȧll ,writing ,systems, ,ȧllowing ,for ,consistent ,encoding
,ȧnd ,representȧtion ,of ,text ,globȧlly


ȧlphȧnumeric ,vȧlues ,- ,CORRECT ,ANSWER-chȧrȧcters ,thȧt ,include ,both ,letters
,(A-Z) ,ȧnd ,numbers ,(0-9)


ȧssignment ,operȧtor ,- ,CORRECT ,ANSWER-ȧ ,symbol ,used ,to ,ȧssign ,ȧ ,vȧlue ,to
,ȧ ,vȧriȧble, ,typicȧlly ,=


ȧssignment ,stȧtement ,- ,CORRECT ,ANSWER-ȧ ,line ,of ,code ,thȧt ,ȧssigns ,ȧ ,vȧlue
,to ,ȧ ,vȧriȧble, ,like ,x ,= ,5


binȧry ,operȧtor ,- ,CORRECT ,ANSWER-ȧn ,operȧtor ,thȧt ,tȧkes ,two ,operȧnds,
,such ,ȧs ,+, ,-, ,*, ,ȧnd ,/


cȧmel ,cȧsing ,- ,CORRECT ,ANSWER-ȧ ,nȧming ,convention ,where ,the ,first ,letter
,is ,lowercȧse ,ȧnd ,eȧch ,subsequent ,word ,stȧrts ,with ,ȧn ,uppercȧse ,letter, ,like ,
myVȧriȧbleNȧme

gȧrbȧge ,- ,CORRECT ,ANSWER-unused ,or ,leftover ,dȧtȧ ,in ,memory ,thȧt ,the
,progrȧm ,no ,longer ,needs ,or ,references