Whenever we pronounce the word comet, the first name that appears in our minds is the Halley's comet. Named after Edmond Halley, who predicted that this comet would appear once in every 76 years.
But that is not accurate as the Halley's comet does not return exactly in 76 years. The gravitational pull of the major planets alters the orbital period from revolution to revolution. Nongravitational effects like the reaction from gasses boiled off during its passage near sun also play an important, but smaller role in altering its orbit.
Between the years 239 BC and 1986 AD the orbital period has varied from 76.0 years to 79.3 years. The closest perihelion passage to the time of Jesus are 11 BC and 66 AD, neither event took place in Jesus' lifetime. In 1066 it appeared during the Battle of Hastings, which is considered as its famous appearence.
Comet Halley was visible in 1910 and again in 1986. Its next perihelion passage will be in early 2062.
Halley's orbit is retrograde and inclined 18 degrees to the ecliptic. And, like all comets, highly eccentric.
Halley is almost unique among comets in that it is both large and active and has a well defined, regular orbit. This made it relatively easy to target. Comet Halley will return to inner solar system in the year 2061.
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