In Greek mythology, Telemachus (also transliterated as Telemachos or Telémakhos) was the son of Odysseus and Penelope. His part in the saga of Odysseus was described by Homer in the Odyssey.
After his father had been gone for nearly 20 years, young Telemachus came of age and was visited by Athena, who disguised herself as Mentor and advised him to travel in search of news of his father. He traveled to Pylos and Lacedaemon. Their rulers, Nestor and Menelaus, were very courteous. Pisistratus accompanied him on this search.
In Ithaca, Penelope was fending off countless suitors. Odysseus returned and disguised himself as an old man or a beggar and saw that she was faithful to him, pretending to knit a burial shroud (for they claimed he must be dead) and claiming she would choose one suitor when she finished. Every night she undid part of the shroud. Odysseus watched the suitors drink and take advantage of his family's hospitality, then took off his disguise and, with Telemachus and Eumaeus the swineherd, killed them all save Medon, who had been polite to Penelope, and Phemius, a local singer who had been forced to help the suitors against Penelope. Alternatively, he (or Penelope at the prompting of Athena) challenged the suitors to an archery contest and killed them after winning. In an alternate version, Odysseus tested his wife's loyalty by claiming she had moved their bed (which had a tree as a bedpost). She denied doing so and Odysseus knew she was loyal.