what is a midi keyboard controller

{"title":"MIDI Keyboard DIN Power Cable 28AWG Wire Gauge PVC Jacket Copper Conductor","imgUrl":"https:\/\/img.chinax.com\/nimg\/55\/1f\/90ceb051d98f3758a9c5649a60f0-200x200-1.jpg","attrs":{"Price":"Ask for lasted price","Brand Name":"KBTech","Model Number":"5PIN DIN Y CABLE","Minimum Order Quantity":"500","Delivery Time":"7-10 working days","Certification":"ROHS ,CE,UL","Place of Origin":"China","Payment Terms":"T\/T, Western Union,Paypal, MoneyGram","Supply Ability":"5000pcs per week","Packaging Details":"1. one piece in a poly bag;2. 200-250pcs in a export carton","Length":"50CM or custom","Color":"Black","Connector end":"5pin din male to female","Conductor":"Copper","Wire guage":"28AWG","Jacket":"PVC","Use":"MIDI keyboard (synthesizer, organ, electric piano, MIDI guitar)","Warranty":"12 Months"}}

{"title":"Conference Video Camera PTZ Joystick Keyboard Controller Temperature -70 490C Control","imgUrl":"https:\/\/img.chinax.com\/nimg\/3e\/d2\/8e8d83b3d46ce993e9f5a313f844-200x200-1.jpg","attrs":{"Price":"$350.00\/pieces >=1 pieces","Brand Name":"TCHD","Model Number":"UV1000","Full Size keyboard":"Yes","Features":"Plug and Play","Operation Style":"Mechanical","Drive Interface":"PS\/2","Private Mold":"NO","Style":"Standard","Type":"Wired","Interface Type":"Other","Keyboard Standard":"Mini Keyboard","Products Status":"New, Stock","Application":"Desktop","Place of Origin":"Beijing, China","Axis Body Brand":"Others","Keyboard backlit":"NO","Product name":"joystick controller","Key":"constant open key","Joystick":"3-axis joystick, home position automatically","Digital display":"12864 LCD display","Temperature":"-70 ~ 490C","Humidity":"10 ~ 90%","Dimension":"Length (34) x width (18) x height (5) CM","Weight":"1.5kg","Input voltage":"12VDC","Certification":"FCC, CE","Supply Ability":"100 Piece\/Pieces per Month"}}

{"title":"61 KEYS Standard Electronic keyboard Piano touch response keyboard with MIDI out ARK-2173","imgUrl":"https:\/\/img.chinax.com\/nimg\/7d\/f8\/1345d827c9d7910e7f956da4a2d2-200x200-1.jpg","attrs":{"Price":"FOB Shanghai US$30~40","Brand Name":"AGOS","Model Number":"ARK-2173","Minimum Order Quantity":"100PCS","Delivery Time":"30 days","Place of Origin":"China","Certification":"CE, ISO9001:2000, LVD, EMC,CCC","Packaging Details":"White box \/ Factory's Color Box \/ OEM box with extra cost","Payment Terms":"T\/T; L\/C"}}