Allah say`s وَاعْبُدُوا اللّٰهَ وَلَا تُشْرِكُوْا بِهٖ شَـيْـــــًٔـا
“Worship Allah, and join not any partners with Him”
In this Verse Allah Almighty command us to worship him only, it means that we cannot worship other than Allah Almighty.
Our beloved prophet Mohammad (pbuh)
إِنَّ الدُّعَائَ هُوَ الْعِبَادَةُ : said
“Indeed the supplication is the worship"(2)
In this Hadith prophet Mohammad (pbuh) told us that supplication (dua) is worship and We recite in our prayers at least 17 times in a day
اِيَّاكَ نَعْبُدُ وَاِيَّاكَ نَسْتَعِيْنُ You alone we only worship, and from You alone we seek help.(3)
قال شیخ السلام ابن تيمية رحمه الله:”بأنھا اسم جامع لکل ما یحبه اللہ و یرضا الأقول و الأعمال الباطنةو الظاھرة“
Sheikh ul Islam Ibn Taymiyya said:Worship (Al-'Ibadah) is a comprehensive term covering everything invisible and visible which Allah loves and pleases.
So every action visible and invisible which Allah Almighty loves and pleases such as Charity ,Prayer, Fast, Haj….and words like reading Quran, supplication دعاor remembering Allah in Heart..... all comes in worship so it should be done to please and get reward from Allah by love, fearing and hope.
Allah say`s in the Quran: "They worship, besides Allah, the objects that have no power to give them anything from the heavens and the earth, nor can they ever have such power”
What will happen if we worship other then Allah Almighty? As per QUAN and HADITH we are obliged to worship Allah Almighty only and not to make partner with him . Lets take simple example if A and B invest 1 lakh to start a business with capitals of equal amount they are called equal partner similarly if you worship Allah and stone ,grave ,tree ,sun........you are making (same stone...and Allah Almighty) partner to Allah Almighty and it is shirk } شركpolytheism} as we read in first verse  because stone, sun, person, prophet ......cannot give you any thing it is Allah Almighty who gives and Allah Says in the Quran: "Surely Allah does not forgive that anything should be associated with Him(5)”
If we associate partner with Allah and died before repent we will be thrown to hell for ever.
وآخر الحد للہ رب العلین
For more details log on to www.AoQuran.in/tawheed
1 Al Quran 4:36
2 Sunen Abu Dawood Book one Hadith No. 1475 Authentic)