Most countries in the world have their own currency. Each currency is controlled by a government (or sometimes a group of countries), it is controlled for the benefit of that country.
Here is a list:
Currency; ISO code; Country or countries using currency
Afghan afghani; AFN; Afghanistan
Albanian lek; ALL; Albania
Algerian dinar; DZD; Algeria
Angolan kwanza; AOA; Angola
Argentine peso; ARS; Argentina
Armenian dram; AMD; Armenia, Nagorno-Karabakh Republic
Aruban florin; AWG; Aruba
Australian dollar; AUD; Australia, Cocos (Keeling) Islands, Kiribati, Nauru, Tuvalu
Azerbaijani manat; AZN; Azerbaijan
Bahamian dollar; BSD; The Bahamas
Bahraini dinar; BHD; Bahrain
Bangladeshi taka; BDT; Bangladesh
Barbadian dollar; BBD; Barbados
Belarusian ruble; BYR; Belarus
Belize dollar; BZD; Belize
Bermudian dollar; BMD; Bermuda
Bhutanese ngultrum; BTN; Bhutan
Bolivian boliviano; BOB; Bolivia
Bosnia and Herzegovina convertible mark; BAM; Bosnia and Herzegovina
Botswana pula; BWP; Botswana
Brazilian real; BRL; Brazil
British pound; GBP; United Kingdom, Alderney, Falkland Islands, Gibraltar, Guernsey, Isle of Man, Jersey, Saint Helena, Tristan da Cunha
Brunei dollar; BND; Brunei
Brunei dollar; BND; Singapore
Bulgarian lev; BGN; Bulgaria
Burmese kyat; MMK; Burma
Burundian franc; BIF; Burundi
Cambodian riel; KHR; Cambodia
Canadian dollar; CAD; Canada
Cape Verdean escudo; CVE; Cape Verde
Cayman Islands dollar; KYD; Cayman Islands
Central African CFA franc; XAF; Cameroon, Central African Republic, Chad, Republic of the Congo, Equatorial Guinea, Gabon
CFP franc; XPF; French Polynesia, New Caledonia, Wallis and Futuna
Chilean peso; CLP; Chile
Chinese yuan; CNY; People's Republic of China
Colombian peso; COP; Colombia
Comorian franc; KMF; Comoros
Congolese franc; CDF; Democratic Republic of the Congo
Costa Rican colón; CRC; Costa Rica
Croatian kuna; HRK; Croatia
Cuban convertible peso; CUC; Cuba
Cuban peso; CUP; Cuba
Czech koruna; CZK; Czech Republic
Danish krone; DKK; Denmark, Faroe Islands
Djiboutian franc; DJF; Djibouti
Dominican peso; DOP; Dominican Republic
East Caribbean dollar; XCD; Anguilla, Antigua and Barbuda, Dominica, Grenada, Montserrat, Saint Kitts and Nevis, Saint Lucia, Saint Vincent and the Grenadines
Egyptian pound; EGP; Egypt
Eritrean nakfa; ERN; Eritrea
Ethiopian birr; ETB; Ethiopia
Euro; EUR; Andorra, Austria, Belgium, Cyprus, Estonia, Finland, France, Germany, Greece, Ireland, Italy, Kosovo, Luxembourg, Malta, Monaco, Montenegro, Netherlands, Portugal, San Marino, Slovakia, Slovenia, Spain, Vatican City
Fijian dollar; FJD; Fiji
Gambian dalasi; GMD; The Gambia
Georgian lari; GEL; Georgia
Ghana cedi; GHS; Ghana
Guatemalan quetzal; GTQ; Guatemala
Guinean franc; GNF; Guinea
Guyanese dollar; GYD; Guyana
Haitian gourde; HTG; Haiti
Honduran lempira; HNL; Honduras
Hong Kong dollar; HKD; Hong Kong (China)
Hungarian forint; HUF; Hungary
Icelandic króna; ISK; Iceland
Indian rupee; INR; India
Indonesian rupiah; IDR; Indonesia
Iranian rial; IRR; Iran
Iraqi dinar; IQD; Iraq
Israeli new shekel; ILS; Israel, Palestine
Jamaican dollar; JMD; Jamaica
Japanese yen; JPY; Japan
Jordanian dinar; JOD; Jordan
Jordanian dinar; JOD; Palestine
Kazakhstani tenge; KZT; Kazakhstan
Kenyan shilling; KES; Kenya
Kuwaiti dinar; KWD; Kuwait
Kyrgyzstani som; KGS; Kyrgyzstan
Lao kip; LAK; Laos
Latvian lats; LVL; Latvia
Lebanese pound; LBP; Lebanon
Lesotho loti; LSL; Lesotho
Liberian dollar; LRD; Liberia
Libyan dinar; LYD; Libya
Lithuanian litas; LTL; Lithuania
Macanese pataca; MOP; Macau (China)
Macedonian denar; MKD; Macedonia
Malagasy ariary; MGA; Madagascar
Malawian kwacha; MWK; Malawi
Malaysian ringgit; MYR; Malaysia
Maldivian rufiyaa; MVR; Maldives
Mauritanian ouguiya; MRO; Mauritania
Mauritian rupee; MUR; Mauritius
Mexican peso; MXN; Mexico
Moldovan leu; MDL; Moldova
Mongolian tögrög; MNT; Mongolia
Moroccan dirham; MAD; Morocco
Mozambican metical; MZN; Mozambique
Namibian dollar; NAD; Namibia
Nepalese rupee; NPR; Nepal
Netherlands Antillean guilder; ANG; Curaçao
Netherlands Antillean guilder; ANG; Sint Maarten
New Taiwan dollar; TWD; Taiwan (Republic of China)
New Zealand dollar; NZD; New Zealand, Cook Islands, Niue, Pitcairn Islands
Nicaraguan córdoba; NIO; Nicaragua
Nigerian naira; NGN; Nigeria
North Korean won; KPW; North Korea
Norwegian krone; NOK; Norway
Omani rial; OMR; Oman
Pakistani rupee; PKR; Pakistan
Panamanian balboa; PAB; Panama
Papua New Guinean kina; PGK; Papua New Guinea
Paraguayan guaraní; PYG; Paraguay
Peruvian nuevo sol; PEN; Peru
Philippine peso; PHP; Philippines
Polish złoty; PLN; Poland
Qatari riyal; QAR; Qatar
Romanian leu; RON; Romania
Russian ruble; RUB; Russia, Abkhazia, South Ossetia
Rwandan franc; RWF; Rwanda
Salvadoran colón; SVC; El Salvador
Samoan tālā; WST; Samoa
São Tomé and Príncipe dobra; STD; São Tomé and Príncipe
Saudi riyal; SAR; Saudi Arabia
Serbian dinar; RSD; Serbia
Seychellois rupee; SCR; Seychelles
Sierra Leonean leone; SLL; Sierra Leone
Singapore dollar; SGD; Singapore, Brunei
Solomon Islands dollar; SBD; Solomon Islands
Somali shilling; SOS; Somalia
Somaliland shilling; None; Somaliland
South African rand; ZAR; South Africa, Namibia, Zimbabwe
South Korean won; KRW; South Korea
South Sudanese pound; SSP; South Sudan
Sri Lankan rupee; LKR; Sri Lanka
Sudanese pound; SDG; Sudan
Surinamese dollar; SRD; Suriname
Swazi lilangeni; SZL; Swaziland
Swedish krona; SEK; Sweden
Swiss franc; CHF; Switzerland, Liechtenstein
Syrian pound; SYP; Syria
Tajikistani somoni; TJS; Tajikistan
Tanzanian shilling; TZS; Tanzania
Thai baht; THB; Thailand
Tongan paʻanga; TOP; Tonga
Transnistrian ruble; None; Transnistria
Trinidad and Tobago dollar; TTD; Trinidad and Tobago
Tunisian dinar; TND; Tunisia
Turkish lira; TRY; Turkey, Northern Cyprus
Turkmenistan manat; TMT; Turkmenistan
Ugandan shilling; UGX; Uganda
Ukrainian hryvnia; UAH; Ukraine
United Arab Emirates dirham; AED; United Arab Emirates
United States dollar; USD; United States, Bonaire, British Indian Ocean Territory, British Virgin Islands, East Timor, Ecuador, El Salvador, Marshall Islands, Micronesia, Palau, Panama, Saba, Sint Eustatius, Turks and Caicos Islands
Uruguayan peso; UYU; Uruguay
Uzbekistani som; UZS; Uzbekistan
Vanuatu vatu; VUV; Vanuatu
Venezuelan bolívar; VEF; Venezuela
Vietnamese đồng; VND; Vietnam
West African CFA franc; XOF; Benin, Burkina Faso, Côte d'Ivoire, Guinea-Bissau, Mali, Niger, Senegal, Togo
Yemeni rial; YER; Yemen
Zambian kwacha; ZMK; Zambia