Injin yana da bambanci kuma ana iya rarraba su ta hanyoyi da yawa, kamar: ta hanyar aiki (injin wuta, injin sarrafa kayan aiki, injin murkushewa, da sauransu); ta masana'antu (na'urorin aikin gona, injinan ma'adinai, injin ɗin yadi, da dai sauransu); kuma ta hanyar ka'idar aiki (na'urorin thermal, injin ruwa, injin bionic, da sauransu).
Bugu da ƙari, inji yana ɗaukar matakai da yawa tare da ayyuka daban-daban yayin bincike, haɓakawa, ƙira, masana'anta, da aikace-aikacensa. Dangane da waɗannan matakai daban-daban, ana iya ƙara aikin injiniyan injiniya zuwa wasu tsarin haɗin kai da ma'amala, kamar binciken injiniya, ƙirar injina, masana'anta, da aikace-aikacen injina da kiyayewa.
Waɗannan ƙa'idodi daban-daban na -, waɗanda aka rarraba su ta fuskoki daban-daban, tsaka-tsaki da haɗuwa, masu yuwuwar haifar da ɗaruruwan ƙasƙanci{1}} horo a cikin injiniyan injiniya. Misali, injunan wuta, wanda aka karkasa su ta hanyar aiki, yana da hadaddun dangantaka mai rikitarwa tare da wasu ƙa'idodin- ladabtarwa kamar injinan zafi, injinan ruwa, injin turbine, injuna mai jujjuyawa, injin wutan tururi, tashoshin makamashin nukiliya, injunan konewa na ciki, da injin turbin gas, gami da ƙananan injina, da injin turbin gas, gami da ƙananan injiniyoyi, injiniyoyin lantarki, injiniyoyin lantarki, injiniyoyin lantarki, injiniyoyin lantarki, injin injin lantarki, injin jirgin ruwa na tsakiya, injin injin lantarki, injin injin lantarki, injin injin lantarki, injin injin lantarki, injin injin lantarki, injin injin lantarki, injin lantarki, injin injin lantarki, injin injin wutan lantarki, injin lantarki, injin injin lantarki, injin injin lantarki, injin injin lantarki, injin injin lantarki, injin injin lantarki, injin injin lantarki, injin injin lantarki, injin injin lantarki, injin injin lantarki, injin injin lantarki, injin injin lantarki, injin injin lantarki, injin injin lantarki, injin injin lantarki, da injin injin injin lantarki, da injin injin wuta, da injin injin wuta, da injin injin wuta, da injin injin gas, da na ƙasa-. da injiniyan motoci. Injin tururi na ruwa injinan wuta ne, da injinan zafi, injinan ruwa, da injin turbin. Suna cikin masana'antar samar da wutar lantarki ta ruwa, masana'antar sarrafa tururi, kuma suna iya kasancewa na tashoshin makamashin nukiliya, da sauransu.
