glitches are bugs in games the creator have know idea about but they can be good or bad

there are good (ex. missingno. clone glitch rare candy glitch etc) but there are bad ones (ex. female symbol bad egg) most are neutral

lots of people mistake new glitches as missingno or look like missingno. ex. 'M' so lots of people just call them missingno.

people often like to search for them using gameshark or emulators yet many ether crash the game repeat hatching or corrupt your save and delete your file.