An Index or Indices measures the performance of an asset class, such as equity, commodity or currency.

An Stock market Index can use a price-weighted formula such as the Dow Jones Industrial Average, NYSE Arca Major Market Index, and the NYSE ARCA Tech 100 Index or a capitalization-weighted Index also called market-value-weighted  such as 

A Commodity  index is a price-weighted or weighted average of a basket of commodities. The Commodity Indices are often traded on exchanges.

Commodity Indices or Commodity Indexes are the same thing.

A Bond Index or Bond market Index, most of the time it has its own calculation methodology.

Bond market Index may be used to compare the return on specific investments.

Bond Indices or Bond Indexes are the same thing.

Examples of Currency Indices:

USD Index

EUR Index or Euro Index

AUD Index

GBP Index

JPY Index

CAD Index

NZD Index

CHF Index

Examples of Commodity Indexes:

World Bank Commodity Price Index

Continuous Commodity Index (CCI)

Dow Jones-UBS Commodity Index

Goldman Sachs Commodity Index (S&P GSCI)

Thomson Reuters/Jefferies CRB Index (TR/CC CRB)

Rogers International Commodity Index (RICI)

Standard & Poor's Commodity Index (SPCI) 

NCDEX Commodity Index

Deutsche Bank Liquid Commodity Index (DBLCI)

Credit Suisse Commodity Benchmark Index (CSCB)

Merrill Lynch Commodity index eXtra (MLCX)

Astmax Commodity Index(AMCI)

UBS Bloomberg Constant Maturity Commodity Index (CMCI)

SummerHaven Dynamic Commodity Index (SDCI)

Examples of Stock market Indices:

Dow Jones Industrial Average

S&P 500 Composite

Nasdaq Composite

Nikkei 225 - 日経225
TOPIX - 東証株価指数

FTSE 100

Dax 30

CAC 40

ASX 200

Australia All Ordinaries - ASX 500 

India Bombay Stock Exchange(BSE) - Sensex

Israel TA-100 Index 

Italy MIBTel

Hang Seng Index 恆指 - 恒生指數

China SSE Composite Index - 中國上證綜合指數

China CSI 300 Index - 中國CSI 300指數

Canada S&P/TSX 60

Canada S&P/TSX Composite Index

Spanish - IBEX 35

Kuala Lumpur Composite Index (KLCI)

Taiwan Capitalization Weighted Stock Index (TAIEX)

MSCI EAFE

KOSPI

KOSDAQ

Swiss Market Index (SMI)

Sweden OMX Stockholm 30 (OMXS30)

Finland OMX Helsinki 25

Denmark OMX Copenhagen 20

Belgium BEL20

Austria ATX

S&P Sri Lanka 20 (S&P SL20)

Netherlands AEX index

Norway OBX Index

Pakistan KSE 100 Index

Portugal PSI-20

Romania BET-10

Examples of Bond market Indices:

Bank of America Merrill Lynch Global Bond Index

Barclays Capital Aggregate Bond Index former Barclays Capital Aggregate Bond Index or Lehman Aggregate Bond Index

Citi World Broad Investment - Grade Bond Index (World BIG)

Merrill Lynch Domestic Master Bond index

Lehman Brothers US Treasury Index

Capital Markets Bond Index (^CPMKTB)

US Broad Investment - Grade Bond Index (USBIG)

Barclays Inflation - Linked Euro Government Bond Index

World Government Bond Index (WGBI)

FTSE Actuaries UK Gilts Indices

J.P. Morgan Government Bond Index