Meteoroids are small near-Earth objects (< 10 m) which can be detected as meteors in the Earth's atmosphere. Meteor observations provide us with meteoroid orbits and can be also used to infer physical properties and chemical composition of meteoroids. Most meteoroids are fragments of either comets or asteroids. Direct link to the actual parent body is possible in case of meteoroid streams. In other cases, the type of orbit can indicate the asteroidal or cometary origin of the meteoroid. In this review, the properties (structure, mechanical strength, composition) of parent comets and asteroids will be discussed on the basis of meteor observations. The alternation of meteoroids in interplanetary space will be also discussed. Perseid and Leonid streams are typical representatives of cometary dust material originating in Halley type comets. Cometary dust can be characterized by low strength, low density (< 1 g /cm3) and high porosity. The Fe/Mg ratio is lower than chondritic. There are, however, mm-sized pieces of material embedded in comets with much higher strength. Also the irradiation cometary crust is much stronger than normal cometary material. The crust is also altered chemically, being depleted in Na. The Giacobinid stream is a representative of Jupiter family cometary material. This material seems to be even weaker than the Halley-type material. The Taurid meteoroid complex is related to comet Encke and possibly to several asteroids. The parent body of the Geminid stream is asteroid 3200 Phaethon. The Geminid meteoroids are significantly stronger than typical cometary meteoroids and are depleted in Na but this is a consequence of low perihelion distance of the stream (0.14 AU). The Fe/Mg ratio of Geminids is cometary and Phaethon is likely an extinct comet. Similar situation is with the Quadrantid stream and its parent asteroid 2003 EH1. The asteroidal meteoroids are, of course, stronger than cometary ones; nevertheless, they are much weaker than recovered meteorites because they contain large scale cracks.