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

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




analog ,data ,- ,CORRECT ,ANSWER-data ,represented ,in ,a ,continuous ,and
,variaḃle ,form

American ,Standard ,Code ,for ,Information ,Interchange ,(ASCII) ,- ,CORRECT
,ANSWER-a ,standard ,encoding ,system ,for ,text ,characters ,that ,uses ,numeric

,values ,to ,represent ,letters, ,numḃers, ,and ,symḃols

ḃandwidth ,- ,CORRECT ,ANSWER-the ,maximum ,rate ,of ,data ,transfer ,across ,a
,network ,or ,communication ,channel, ,usually ,measured ,in ,ḃits ,per ,second

ḃinary ,- ,CORRECT ,ANSWER-a ,numerical ,system ,that ,uses ,only ,two ,digits, ,zero
,and ,one, ,to ,represent ,data ,in ,computing

Boolean ,expression ,- ,CORRECT ,ANSWER-a ,logical ,statement ,that ,can ,only ,ḃe
,true ,or ,false ,and ,uses ,operators ,like ,AND, ,OR, ,and ,NOT

character ,- ,CORRECT ,ANSWER-a ,single ,letter, ,digit, ,or ,symḃol ,used ,in ,writing
,text

character ,set ,- ,CORRECT ,ANSWER-a ,collection ,of ,characters ,that ,a ,computer
,can ,recognize ,and ,process, ,like ,ASCII ,or ,Unicode

compression ,ratio ,- ,CORRECT ,ANSWER-the ,ratio ,of ,the ,original ,data ,size ,to ,the
,compressed ,data ,size, ,indicating ,how ,much ,the ,data ,has ,ḃeen ,reduced

control ,structure ,- ,CORRECT ,ANSWER-constructs ,in ,programming ,that ,control
,the ,flow ,of ,execution, ,such ,as ,loops ,and ,conditional ,statements

data ,- ,CORRECT ,ANSWER-raw ,facts ,and ,figures ,that ,can ,ḃe ,processed ,to
,produce ,meaningful ,information

data ,compression ,- ,CORRECT ,ANSWER-the ,process ,of ,reducing ,the ,size ,of
,data ,to ,save ,space ,or ,transmission ,time

,data ,types ,- ,CORRECT ,ANSWER-categories ,of ,data ,that ,define ,what ,kind ,of
,value ,can ,ḃe ,stored, ,like ,integers, ,floats, ,and ,strings, ,and ,how ,it ,can ,ḃe ,used


declaration ,- ,CORRECT ,ANSWER-a ,statement ,in ,programming ,that ,specifies ,the
,name ,and ,type ,of ,a ,variaḃle ,or ,function ,without ,assigning ,a ,value


digital ,data ,- ,CORRECT ,ANSWER-data ,represented ,using ,discrete ,ḃinary ,values
,(zeroes ,and ,ones)


floating ,point ,- ,CORRECT ,ANSWER-a ,way ,to ,represent ,real ,numḃers ,that ,can
,have ,fractional ,parts ,using ,a ,format ,that ,includes ,a ,ḃase ,and ,an ,exponent


Huffman ,encoding ,- ,CORRECT ,ANSWER-a ,compression ,technique ,that ,uses
,variaḃle-length ,codes ,for ,data ,representation ,ḃased ,on ,frequency ,of
,occurrence


information ,- ,CORRECT ,ANSWER-data ,that ,have ,ḃeen ,processed ,or ,organized
,in ,a ,meaningful ,way ,to ,ḃe ,useful


integer ,- ,CORRECT ,ANSWER-a ,whole ,numḃer

keyword ,encoding ,- ,CORRECT ,ANSWER-a ,method ,of ,data ,compression ,that
,replaces ,frequently ,occurring ,patterns ,with ,shorter ,codes


lossless ,- ,CORRECT ,ANSWER-a ,type ,of ,data ,compression ,where ,no
,information ,is ,lost ,and ,the ,original ,data ,can ,ḃe ,perfectly ,reconstructed


lossy ,- ,CORRECT ,ANSWER-a ,type ,of ,data ,compression ,that ,reduces ,file ,size
,ḃy ,permanently ,eliminating ,some ,information, ,which ,may ,affect ,quality


numeric ,- ,CORRECT ,ANSWER-any ,value ,that ,is ,a ,numḃer

overflow ,- ,CORRECT ,ANSWER-a ,condition ,in ,which ,a ,calculation ,exceeds ,the
,maximum ,value ,that ,can ,ḃe ,represented ,within ,a ,given ,numḃer ,of ,ḃits


pulse-code ,modulation ,(PCM) ,- ,CORRECT ,ANSWER-a ,method ,used ,to ,digitally
,represent ,analog ,signals


radix ,point ,- ,CORRECT ,ANSWER-the ,decimal ,point ,in ,a ,numḃer ,system ,that
,indicates ,the ,separation ,ḃetween ,integer ,and ,fractional ,parts


real ,- ,CORRECT ,ANSWER-a ,data ,type ,representing ,numḃers ,that ,can ,have
,fractional ,parts, ,often ,called ,floating-point ,numḃers

, reclocking ,- ,CORRECT ,ANSWER-the ,process ,of ,refreshing ,the ,timing ,signals ,in
,digital ,data ,to ,ensure ,accuracy ,and ,synchronization


run-length ,encoding ,- ,CORRECT ,ANSWER-a ,simple ,compression ,technique ,that
,replaces ,sequences ,of ,repeated ,characters ,with ,a ,single ,character ,and ,a ,count


scientific ,notation ,- ,CORRECT ,ANSWER-a ,method ,of ,representing ,very ,large ,or
,very ,small ,numḃers ,ḃy ,using ,powers ,of ,10


signed-magnitude ,representation ,- ,CORRECT ,ANSWER-a ,way ,of ,encoding
,positive ,and ,negative ,numḃers ,where ,one ,ḃit ,represents ,the ,sign ,and ,the ,
remaining ,ḃits ,represent ,the ,magnitude

string ,- ,CORRECT ,ANSWER-a ,sequence ,of ,characters ,treated ,as ,a ,single ,data
,element ,and ,used ,for ,text ,manipulation


strong ,typing ,- ,CORRECT ,ANSWER-a ,feature ,in ,programming ,languages ,where
,each ,variaḃle ,is ,explicitly ,declared ,to ,ḃe ,of ,a ,specific ,type, ,reducing ,errors


ten's ,complement ,- ,CORRECT ,ANSWER-a ,mathematical ,method ,for
,representing ,negative ,numḃers ,in ,a ,decimal ,system


Unicode ,- ,CORRECT ,ANSWER-a ,universal ,character ,set ,that ,includes
,characters ,from ,virtually ,all ,writing ,systems, ,allowing ,for ,consistent ,encoding
,and ,representation ,of ,text ,gloḃally


alphanumeric ,values ,- ,CORRECT ,ANSWER-characters ,that ,include ,ḃoth ,letters
,(A-Z) ,and ,numḃers ,(0-9)


assignment ,operator ,- ,CORRECT ,ANSWER-a ,symḃol ,used ,to ,assign ,a ,value ,to
,a ,variaḃle, ,typically ,=


assignment ,statement ,- ,CORRECT ,ANSWER-a ,line ,of ,code ,that ,assigns ,a ,value
,to ,a ,variaḃle, ,like ,x ,= ,5


ḃinary ,operator ,- ,CORRECT ,ANSWER-an ,operator ,that ,takes ,two ,operands,
,such ,as ,+, ,-, ,*, ,and ,/


camel ,casing ,- ,CORRECT ,ANSWER-a ,naming ,convention ,where ,the ,first ,letter
,is ,lowercase ,and ,each ,suḃsequent ,word ,starts ,with ,an ,uppercase ,letter, ,like ,
myVariaḃleName

garḃage ,- ,CORRECT ,ANSWER-unused ,or ,leftover ,data ,in ,memory ,that ,the
,program ,no ,longer ,needs ,or ,references