The clock is regarding one of the oldest human inventions, where it’s meeting the need to measure the time in the natural units, such as second, minute, day, month and the year. However, if you want to measure the time accurately, you’ll need the help of some devices.
Brother Paul has invented the first record of a minute hand on a clock in 1475. Alexander Bain, a Scottish clockmaker was the first inventor that patented the electric clock in 1840! Although the digital clock is one of the most common items in nowadays, but you cannot miss this digital clock:

Digital clock date thermometer with thermostat [Showing time while thermostat active]

It is a small adjustable clock/date/thermometer with thermostat function based on PIC16F628 or PIC16F84 microchip and DS1631 temperature sensor. The hardware part is very simple because it only uses pic microcontroller, the DS1631 sensor, 4x7 segments (common anode, something like KW4-301xxx Series), four 2N3906 transistors, some rezistors!

Note: Do not place DS1631 near heat providers, best thing is to let it float in the air while is connected through isolated wires. Project using PIC16F84 does not have tt, td, tE options because it didn't have enough space for the code. For more information about these options see » How it works page.