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The Father of Modern Periodic Table was Russian professor of chemistry "Dimitri Ivanovich Mendeleev" in 1923. This modern periodic table also known long form of periodic table .

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Modern Periodic Table - Introduction | Classification of Elements | Don't Memorise

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The periodic table has undergone extensive changes in the time since it was originally developed by Mendeleev and Moseley in 1869. The periodic table based on Atomic Mass.  There occurs Many limitations for Mendeleev period table. Afterwards the Modern Periodic Table discovered. Many new elements have been discovered, while others have been artificially synthesized.  Each fits properly into a group of elements with similar properties.  In the Modern Periodic Table  is an arrangement of the elements in order of their atomic numbers so that elements with similar properties appear in the same vertical column or group.
The modern periodic law states that the physical and chemical properties of the elements are the periodic functions of their atomic numbers. Scientists arranged elements in increasing order of their atomic numbers from left to right across each row. And discovered that the elements having similar properties repeat after regular intervals.The modern periodic table is the present form of the periodic table. And it consists of 18 vertical columns and 7 horizontal rows.

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A period is a horizontal row of the periodic table.  There are seven periods in the periodic table, with each one beginning at the far left.  A new period begins when a new principal energy level begins filling with electrons.  Period 1 has only twoelements (hydrogen and helium), while periods 2 and 3 have 8 elements.  Periods 4 and 5 have 18 elements.
Periods 6 and 7 have 32 elements because the two bottom rows that are separated from the rest of the table belong to those periods.  They are pulled out in order to make the table itself fit more easily onto a single page.Lanthanides and Actinides.
A group is a vertical column of the periodic table, based on the organization of the outer shell electrons.  There are a total of 18 groups. These include 2 groups of S block elements, 6 groups of p block elements and10 groups of d block elements

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Lanthanides and Actinides are located at the bottom of the periodical table is because of their properties and in the block in which electrons fill up. The lanthanides include elements 58 to 71 (fill out the 4f subshell) and the actinides include elements 89 to 103 (fill out the 5f subshell). These are also know as inner transition elements. They show different properties from transition elements  and some new elements are discovering and keep these group. These elements when put in the group the table become wider.

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Periodic trends are specific patterns in the properties of chemical elements that are revealed in the periodic table of elements. Major periodic trends were atomic radii electronegativity, ionization energy, electron affinity,  ionic radius, metallic character, and chemical reactivity. Periodic trends from the changes in the atomic structure of the chemical elements within their respective periods (horizontal rows) and groups in the periodic table. These laws enable the chemical elements to be organized in the periodic table based on their atomic structures and properties. Due to the periodic trends, the unknown properties of any element can be partially known.

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Electronegativity

Electronegativity is a measure of an atom's ability to attract shared electrons to itself.
On the periodic table, electronegativity generally increases as you move from left to right across a period and decreases as you move down a group.

Atomic Radius

The atomic radius is the distance from the atomic nucleus to the outermost stable electron orbital in an atom that is at equilibrium. The atomic radius tends to decrease across a period from left to right due to the shrinking of the atom because of increasing effective nuclear force on the electrons. The atomic radius usually increases while going down a group due to the addition of a new energy level (shell which causes shrinkage in the size of the atom).

Electronic Affinity

The electron affinity of an atom can be described either as the energy released by an atom when an electron is added to it, conversely as the energy required to detach an electron from a singly charged anion. Electron affinity generally increases across a period in the periodic table and sometimes decreases down a group. These trends are not necessarily universal. The chemical rationale for changes in electron affinity across the periodic table is the increased effective nuclear charge across a period and up a group.

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Ionization Energy

The ionization potential is the minimum amount of energy required to remove one electron. Ionization energy decreases as we go down a group. Ionization energy increases from left to right across the periodic table.

Metallic & Non-Metallic

Metallic properties increase down groups as decreasing attraction between the nuclei and the outermost electrons causes the outermost electrons to be loosely bound and thus able to conduct heat and electricity. Across the period, from left to right, increasing attraction between the nuclei and the outermost electrons causes the metallic character to decrease.

Non-metallic property increases across   a   period and decreases down the group due to the same reason due to an increase in nuclear attractive force. Metals are ductile while nonmetals are not.

Valency

The valence or valency of an element is a measure of its combining power with other atoms when it forms chemical compounds or molecules. Valency in the periodic table across a period first increases and then decreases. There is no change going down a group.

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ADVANTAGES OF THE PERIODIC TABLE:

It is easier to remember the properties of an element if its position in the periodic table is known.

The periodic table has made the study of chemistry systematic and easy. It acts as an aid to memory.

The type of compounds formed by an element can be predicted by knowing it position in the periodic table.

DISADVANTAGESOF  MODERN PERIODIC TABLE

Position of hydrogen is not satisfactory, it can be placed either in group I or 17 group of the first period.

It fails to accommodate lathanides and actinides in the main body of the periodic table. These are kept separately at the bottom of the periodic table.